New LT1 for 2014 6.2l alum block
11-25-2012 | 09:43 PM
#261
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DrkPhx excellent question,
This particular ECM is a work of art also state of the art and extremely complex with variables. It does have self tuning abilities to cope with increased air density and fuel types. However as I've before stated tuning the FUEL TABLES are completely off limits for your safety and the vehicle.
To give you better understanding of the dynamics such as modifications such (COLD AIR INTAKE, HEADERS, ETC) I will have explain in great details the what is happening in the combustion cycle and where the power is made and how things are put out of sync by bolt on's effecting everything.
Let’s start with the exhaust/headers and put things into perspective DrkPhx.
Commonly said the ENGINE is an AIR PUMP that is 30% true. Truly the Engine is an Air Pressure System of velocity, volume density, expansion, and scavenging pressures to reduce volumes of gas once the expansion process is complete. Liquids, Vapor Gases like to move from High pressure to low pressure. There are very few that understand the exhaust process I will do my best to explain in simple terms. Things are very proprietary with the 2014 LT1. So I will have to explain using the LS7. I hope you do not mind but the engine fits the order for the effects.
The best header/manifolds in my opinion are the LS7/LS9. Equal length and smooth exhaust pulses/air low air pressure waves, the short exhaust runners lower the EGT on all 8 cylinders. Below the manifold to the exhaust is where things can be improved. However when someone adds headers to the LS7, sure it picks up HP but the unequal length headers spikes the EGT at 1/2 -WOT due to enrichment through tuning, high lift cams rates and increase air velocity and volume. Reliability is now for certain a problem. Since all metals melt, deflect and deform under excessive hot temperatures its obvious and noted damage to the engine is 100% certain. Installing full length headers by those that say they are equal length suffer from velocity problems due to over sizing tubing which causes deceleration of the gas exiting the exhaust valves causing things heat up. This is now a compound restriction, the valves heats up, deform slightly and then let go DROPPED VALVE consequences destroying the engine. In other engines the piston with the longest exhaust runner on the header heats up and the piston expands and cracks the ring landing over time it breaks, melting, burning, holes, cracking with subjecting these cylinders to higher temperatures than other cylinders you will see failures for certain due to heat stress/unequal EGT. Catastrophic damage is certain over cumulative time.
This is because the low pressure in the exhaust system is out of sync and high temp stress the pistons, cylinder head, block...etc.... Remember Vapors and Gas likes to move from High pressure to low pressure. I will go out on a limb and say most if not ALL aftermarket headers reduce airflow through the engine resulting in some type of a heat stress condition while working the engine hard, some just perform the job better than others removing it. My opinion is spend as much time on your exhaust as you do blue printing your block and heads. What good is a powerful engine if has little or no reliability or has to be rebuilt regularly?
Air Fuel Ratio is commonly used to tune cars; you can have your PCM tuned to the perfect Air Fuel Ratio, and still run into detonation and suffer engine damage. Too much afterburning occurring on at 1/2 - WOT in the Headers. However EGT tuning is better in my expert opinion although Air Fuel Ratios should be monitored as well through a wide band.
Too much air is real problem and issue when cylinder heads are ported for increase volume NOT FLOW... Velocity is everything. It’s called many things in the aftermarket but all it really is the loss ability to burn the additional volume of air and fuel and accelerating it out the exhaust cycle to the exhaust tips. This is really complicated however I will try to explain in a way that is acceptable. Accelerated air has density/mass/drag. Sitting in your home you feel nothing on your arms. Get into your car let down the window and start driving put your arm out the window and you can feel what AIR/GAS really is ...it has density you can now feel it because of the pressure is accelerated known as velocity. Too much velocity = mass/drag and this AIR/GAS becomes thick, dense, and even become lite like syrup liquid that has friction this is now viscosity. Remember as I said earlier the engine is an AIR PRESSURE SYSTEM. The trick you want to perform to gain performance is not to decelerate air density for greater ease of movement from intake to lower pressure exhaust exiting maintains the sync. The pistons convert velocity energy into pressure energy/high gas pressure and even the piston contour shape and temperature is critical. Very few people understand this too much concern is placed on compression rather than pumping the HIGH GAS out the exhaust valve.
Accelerated air velocity is valve angle (FILLED THE CYLINDER QUICKLY) and air volume/density is intake port size, shape and distances traveled. The longer the distance the more you have to take into account temperatures. Flow velocity and volume rate or obtained from vector velocity measurements along a single line of sight valve angles. Which is why in the 2014 LT1, LS7 and LS9 the valve angles are much different than the LS1, LS2, LS3.
This is stated without dealing or factoring other variables however I am only allowed to shine light so to speak. Aftermarket full headers could do major damage if not serious damage to this particular engine. My opinion would be to build onto the exhaust manifold and go back to the exhaust tips. The Cold Air Intake would only stream line the air currents and pressure waves. Wouldn't hurt anything the ECM would notice and adjust continuously as it always does. The volume of air would slightly increase entering the chambers. It would certainly pick up a few horsepower. However this engine loves E85 and the ECM itself is more than capable of bumping up the torque and horsepower through aggressive timing when it burns up E85. This ECM can tune itself that’s for certain. This is a high compression engine and it gets aggressive on e85 or mixing it with 93.
The 2014 LT1 engine is simply amazing. And it has a part time smaller sister and Big Brother coming and Big Brother is downright BRUTAL in power.
Conclusion.... cold air intake YES, Full length headers? Speak to the person or company about low pressure/vacuum effect of their headers. Poorly Designed Headers Destroy ENGINES.
Bigg Gunz
This particular ECM is a work of art also state of the art and extremely complex with variables. It does have self tuning abilities to cope with increased air density and fuel types. However as I've before stated tuning the FUEL TABLES are completely off limits for your safety and the vehicle.
To give you better understanding of the dynamics such as modifications such (COLD AIR INTAKE, HEADERS, ETC) I will have explain in great details the what is happening in the combustion cycle and where the power is made and how things are put out of sync by bolt on's effecting everything.
Let’s start with the exhaust/headers and put things into perspective DrkPhx.
Commonly said the ENGINE is an AIR PUMP that is 30% true. Truly the Engine is an Air Pressure System of velocity, volume density, expansion, and scavenging pressures to reduce volumes of gas once the expansion process is complete. Liquids, Vapor Gases like to move from High pressure to low pressure. There are very few that understand the exhaust process I will do my best to explain in simple terms. Things are very proprietary with the 2014 LT1. So I will have to explain using the LS7. I hope you do not mind but the engine fits the order for the effects.
The best header/manifolds in my opinion are the LS7/LS9. Equal length and smooth exhaust pulses/air low air pressure waves, the short exhaust runners lower the EGT on all 8 cylinders. Below the manifold to the exhaust is where things can be improved. However when someone adds headers to the LS7, sure it picks up HP but the unequal length headers spikes the EGT at 1/2 -WOT due to enrichment through tuning, high lift cams rates and increase air velocity and volume. Reliability is now for certain a problem. Since all metals melt, deflect and deform under excessive hot temperatures its obvious and noted damage to the engine is 100% certain. Installing full length headers by those that say they are equal length suffer from velocity problems due to over sizing tubing which causes deceleration of the gas exiting the exhaust valves causing things heat up. This is now a compound restriction, the valves heats up, deform slightly and then let go DROPPED VALVE consequences destroying the engine. In other engines the piston with the longest exhaust runner on the header heats up and the piston expands and cracks the ring landing over time it breaks, melting, burning, holes, cracking with subjecting these cylinders to higher temperatures than other cylinders you will see failures for certain due to heat stress/unequal EGT. Catastrophic damage is certain over cumulative time.
This is because the low pressure in the exhaust system is out of sync and high temp stress the pistons, cylinder head, block...etc.... Remember Vapors and Gas likes to move from High pressure to low pressure. I will go out on a limb and say most if not ALL aftermarket headers reduce airflow through the engine resulting in some type of a heat stress condition while working the engine hard, some just perform the job better than others removing it. My opinion is spend as much time on your exhaust as you do blue printing your block and heads. What good is a powerful engine if has little or no reliability or has to be rebuilt regularly?
Air Fuel Ratio is commonly used to tune cars; you can have your PCM tuned to the perfect Air Fuel Ratio, and still run into detonation and suffer engine damage. Too much afterburning occurring on at 1/2 - WOT in the Headers. However EGT tuning is better in my expert opinion although Air Fuel Ratios should be monitored as well through a wide band.
Too much air is real problem and issue when cylinder heads are ported for increase volume NOT FLOW... Velocity is everything. It’s called many things in the aftermarket but all it really is the loss ability to burn the additional volume of air and fuel and accelerating it out the exhaust cycle to the exhaust tips. This is really complicated however I will try to explain in a way that is acceptable. Accelerated air has density/mass/drag. Sitting in your home you feel nothing on your arms. Get into your car let down the window and start driving put your arm out the window and you can feel what AIR/GAS really is ...it has density you can now feel it because of the pressure is accelerated known as velocity. Too much velocity = mass/drag and this AIR/GAS becomes thick, dense, and even become lite like syrup liquid that has friction this is now viscosity. Remember as I said earlier the engine is an AIR PRESSURE SYSTEM. The trick you want to perform to gain performance is not to decelerate air density for greater ease of movement from intake to lower pressure exhaust exiting maintains the sync. The pistons convert velocity energy into pressure energy/high gas pressure and even the piston contour shape and temperature is critical. Very few people understand this too much concern is placed on compression rather than pumping the HIGH GAS out the exhaust valve.
Accelerated air velocity is valve angle (FILLED THE CYLINDER QUICKLY) and air volume/density is intake port size, shape and distances traveled. The longer the distance the more you have to take into account temperatures. Flow velocity and volume rate or obtained from vector velocity measurements along a single line of sight valve angles. Which is why in the 2014 LT1, LS7 and LS9 the valve angles are much different than the LS1, LS2, LS3.
This is stated without dealing or factoring other variables however I am only allowed to shine light so to speak. Aftermarket full headers could do major damage if not serious damage to this particular engine. My opinion would be to build onto the exhaust manifold and go back to the exhaust tips. The Cold Air Intake would only stream line the air currents and pressure waves. Wouldn't hurt anything the ECM would notice and adjust continuously as it always does. The volume of air would slightly increase entering the chambers. It would certainly pick up a few horsepower. However this engine loves E85 and the ECM itself is more than capable of bumping up the torque and horsepower through aggressive timing when it burns up E85. This ECM can tune itself that’s for certain. This is a high compression engine and it gets aggressive on e85 or mixing it with 93.
The 2014 LT1 engine is simply amazing. And it has a part time smaller sister and Big Brother coming and Big Brother is downright BRUTAL in power.
Conclusion.... cold air intake YES, Full length headers? Speak to the person or company about low pressure/vacuum effect of their headers. Poorly Designed Headers Destroy ENGINES.
Bigg Gunz
wait... WHAT?
ok back to headers causing higher EGTs... if im reading this right, my LT headers cause more EGT coming out right?
now i have to ask how is that.
Ill give an example that really doesnt make sense then.
On rearmount turbos they have a huge problem of keeping heat inside the pipe all the way to the turbo in the back. Its astually worse to have LT headers because the surface friction and size of LT headers gives off more heat then stock ls1 manifolds, causeing us to wrap our pipes and use stock manifolds in order to keep this heat in throughout the whole hot side.
Now im no genious, but what you said dosnt make any sense. your saying that my LTH's are causing excess heat in the combustion chamber and damaging it? Ive always been taught that LTH's cause a scavanging effect and pull out more exhaust faster throughout the combustion cycle actually cooling it... im confused
11-26-2012 | 07:35 AM
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Removing them will add performance/hp.
Bigg Gunz
11-26-2012 | 08:28 AM
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wait... WHAT?
ok back to headers causing higher EGTs... if im reading this right, my LT headers cause more EGT coming out right?
now i have to ask how is that.
Ill give an example that really doesnt make sense then.
On rearmount turbos they have a huge problem of keeping heat inside the pipe all the way to the turbo in the back. Its astually worse to have LT headers because the surface friction and size of LT headers gives off more heat then stock ls1 manifolds, causeing us to wrap our pipes and use stock manifolds in order to keep this heat in throughout the whole hot side.
Now im no genious, but what you said dosnt make any sense. your saying that my LTH's are causing excess heat in the combustion chamber and damaging it? Ive always been taught that LTH's cause a scavanging effect and pull out more exhaust faster throughout the combustion cycle actually cooling it... im confused
ok back to headers causing higher EGTs... if im reading this right, my LT headers cause more EGT coming out right?
now i have to ask how is that.
Ill give an example that really doesnt make sense then.
On rearmount turbos they have a huge problem of keeping heat inside the pipe all the way to the turbo in the back. Its astually worse to have LT headers because the surface friction and size of LT headers gives off more heat then stock ls1 manifolds, causeing us to wrap our pipes and use stock manifolds in order to keep this heat in throughout the whole hot side.
Now im no genious, but what you said dosnt make any sense. your saying that my LTH's are causing excess heat in the combustion chamber and damaging it? Ive always been taught that LTH's cause a scavanging effect and pull out more exhaust faster throughout the combustion cycle actually cooling it... im confused
Heat is energy okay....wrapping the hot pipes/turbo retains that energy nothing more nothing less. It's keeping that radiant energy from being absorbed by other variables. A rear mount turbo suffers from low velocity drops. The hot side pipe has more than volume to fill than a front mount would. Velocity drives turbos. Warm Air/hot air moves faster and easier than cooler which is why there is a thing called "LAG" and you wrap the hot pipes/tubes to retain that energy. If the right size tubing/pipe is there then basically its building up the pressure to fill the volume and then the volume filled now the air can be accelerated. You are confused because you do not understand the variables. I will try to explain this in a way in which you can understand.
Follow me.... this will go over your head but as I said earlier the ENGINE IS AIR PRESSURE SYSTEM.
Pistons create Low pressure.... by pulling air into the engine. This is when the 30% applies that and engine is an "AIR PUMP." This is vacuum now this empty volume of space has to be filled thanks to the piston. The turbo fills that volume faster and compounds that volume with pressure which is just more air/oxygen faster because of negative pressure in the cylinder. Go back and read when I stated "Air has Density" when accelerated that's what turbos do they pack more density/air /pressure/volume into the space/cylinder which is now in a low pressure zone/vacuum on the BDC. It relates the air pressure, temperature, volume, and mass (pounds) of air. This is all because of velocity/accelerated air speed/velocity. Which is why turbos have pressure MAPS. This is Dynamic Cylinder Pressure for a given engine / Horse Power. And a person or company isn't able to understand a turbo pressure map. They shouldn't be TURBO'ing PERIOD. This is why people in the business are PAID to calculate these factors and recommend a turbo it is all complex math to the average person that just wants to go fast. But back on track...
Heat always flows spontaneously from regions of higher temperature to regions of lower temperature, and never the reverse, unless external work is performed on the system. This heating/heat soak of anything that is cold will absorb heat because at the micro level low pressure areas are formed around any object that is cool/cold. GREAT DESIGN HEADERS will produce LOW PRESSURE/ Vaccuum/Scavenging doing its best to empty the cylinder. This does not create horsepower but it does lower EGT tempertures. Only Dynamic Cylinder Pressure will Created HORSEPOWER.
Bigg Gunz
11-26-2012 | 09:39 AM
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Bigg_Gunz is a classic Engineer. You understand everything you are involved in to such an extent that it's truly and without any doubts impressive. You are, however, unaware of how things work outside of your bubble. Your rant against headers is simply one of the many signs you've given us of that.
You keep doing what you're doing at work and bringing us badass engines from the factory. It sounds like you have a huge role in bringing to life what most of us consider to be the best engine foundations of the modern day. We appreciate it. You should, however, realize that there is life outside of your bubble. The guys in the aftermarket are second to none and they WILL continue to pull more power out of your designs in all of the ways that you claim are impractical or even impossible, including long tube headers and tuning. You work within a set of parameters that the aftermarket does not, like extensive durability testing, emissions standards, fuel efficiency end goals, etc. The aftermarket gets to take the end result of your extensive R&D and toss out the red tape you had to work with.
You keep doing what you're doing at work and bringing us badass engines from the factory. It sounds like you have a huge role in bringing to life what most of us consider to be the best engine foundations of the modern day. We appreciate it. You should, however, realize that there is life outside of your bubble. The guys in the aftermarket are second to none and they WILL continue to pull more power out of your designs in all of the ways that you claim are impractical or even impossible, including long tube headers and tuning. You work within a set of parameters that the aftermarket does not, like extensive durability testing, emissions standards, fuel efficiency end goals, etc. The aftermarket gets to take the end result of your extensive R&D and toss out the red tape you had to work with.
11-26-2012 | 11:22 AM
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Great Designed headers vs poorly designed headers and the function of each is what I was helping him understand that all long tube headers aren't equal. There are many that do more damage than good. The aftermarket has great talent and much respect is given to those that are capable of exceeding OEM designs without question. Although its very few in operation domestically in the United States that can still do it. Alot of them are merged and bought out. However often in OEM development the aftermarket developers are contacted. Think of it as a marriage... we need each other. Basically he asked about adding headers to the 2014 LT1 and I had use the LS7 as an example of what happens with EGT temperatures when "POOR QUALITY HEADERS" are installed. Remember this is only about poor quality headers.... there are very very few aftermarket companies that design "GREAT HEADERS" its more than just making something clear or fit into and engine bay. The low hanging fruit is instant HP gains. The higher cost /consequences are usually dropped valves, cracks in the block liners, heads, piston ring cracking/breaking etc... over cumulative time. There are a Few great aftermarket headers companies in the USA if you are going aftermarket do your homework make the right choice.
Bigg Gunz
Bigg Gunz
11-26-2012 | 02:51 PM
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DrkPhx excellent question,
<snip>.
The best header/manifolds in my opinion are the LS7/LS9. Equal length and smooth exhaust pulses/air low air pressure waves, the short exhaust runners lower the EGT on all 8 cylinders. Below the manifold to the exhaust is where things can be improved. However when someone adds headers to the LS7, sure it picks up HP but the unequal length headers spikes the EGT at 1/2 -WOT due to enrichment through tuning, high lift cams rates and increase air velocity and volume. Reliability is now for certain a problem. Since all metals melt, deflect and deform under excessive hot temperatures its obvious and noted damage to the engine is 100% certain. Installing full length headers by those that say they are equal length suffer from velocity problems due to over sizing tubing which causes deceleration of the gas exiting the exhaust valves causing things heat up.
Companies like QTP, Kooks, American Racing, and others have been racing, developing, and building header systems for years. while yes, over doing it can hurt engine performance, theres plenty of information out there to show that even a 5.7LS series engine can benefit throughout the power band from a 1 7/8" diameter primary tube. without issue. if overall efficiency increases, it seems that the anecdotal evidence points to it being more beneficial than not.
This is now a compound restriction, the valves heats up, deform slightly and then let go DROPPED VALVE consequences destroying the engine. In other engines the piston with the longest exhaust runner on the header heats up and the piston expands and cracks the ring landing over time it breaks, melting, burning, holes, cracking with subjecting these cylinders to higher temperatures than other cylinders you will see failures for certain due to heat stress/unequal EGT. Catastrophic damage is certain over cumulative time.
This is because the low pressure in the exhaust system is out of sync and high temp stress the pistons, cylinder head, block...etc.... Remember Vapors and Gas likes to move from High pressure to low pressure. I will go out on a limb and say most if not ALL aftermarket headers reduce airflow through the engine resulting in some type of a heat stress condition while working the engine hard, some just perform the job better than others removing it. My opinion is spend as much time on your exhaust as you do blue printing your block and heads. What good is a powerful engine if has little or no reliability or has to be rebuilt regularly?
Dropped valves are oem's snafu, not the aftermarket mods. most dropped valves also occcur(ed) on the LS7's. if, IF headers were such a horrible addition and decreased flow and velocity, they would not see the avg gains they do across the broad rpm range. i have only seen LS series engines' pistons go when A) too much boost is applied and it buts the rings and B) the tune on tht given engine is bad. however bad tunes and the like are the risk we take as hotrodders. many MANY builds have done amazing things and are still running just fine given the doom and gloom nature of your outlook.
Air Fuel Ratio is commonly used to tune cars; you can have your PCM tuned to the perfect Air Fuel Ratio, and still run into detonation and suffer engine damage. Too much afterburning occurring on at 1/2 - WOT in the Headers. However EGT tuning is better in my expert opinion although Air Fuel Ratios should be monitored as well through a wide band.
we know. AFR is just one piece of the puzzle. egt tuning in conjunction with AFR tuning is best . however, one can reliably tune an engine without it. knowing how to tune ignition timing is an important part as it has a huge affect not only on egt but how much air fills the cylinder on the next cycle. its certainly as important as being able to tune the overall fueling of the engine. racers read plugs and log egt when possible, nothing new.
Too much air is real problem and issue when cylinder heads are ported for increase volume NOT FLOW... Velocity is everything. It’s called many things in the aftermarket but all it really is the loss ability to burn the additional volume of air and fuel and accelerating it out the exhaust cycle to the exhaust tips. This is really complicated however I will try to explain in a way that is acceptable. Accelerated air has density/mass/drag. Sitting in your home you feel nothing on your arms. Get into your car let down the window and start driving put your arm out the window and you can feel what AIR/GAS really is ...it has density you can now feel it because of the pressure is accelerated known as velocity. Too much velocity = mass/drag and this AIR/GAS becomes thick, dense, and even become lite like syrup liquid that has friction this is now viscosity. Remember as I said earlier the engine is an AIR PRESSURE SYSTEM. The trick you want to perform to gain performance is not to decelerate air density for greater ease of movement from intake to lower pressure exhaust exiting maintains the sync. The pistons convert velocity energy into pressure energy/high gas pressure and even the piston contour shape and temperature is critical. Very few people understand this too much concern is placed on compression rather than pumping the HIGH GAS out the exhaust valve.
Accelerated air velocity is valve angle (FILLED THE CYLINDER QUICKLY) and air volume/density is intake port size, shape and distances traveled. The longer the distance the more you have to take into account temperatures. Flow velocity and volume rate or obtained from vector velocity measurements along a single line of sight valve angles. Which is why in the 2014 LT1, LS7 and LS9 the valve angles are much different than the LS1, LS2, LS3.
i would be willing to bet that companies like WCCH and TEA know exactly what they are doing. however, they are working with what OEM has designed which means compromising in lots of places. yes, a bad porting job will hurt the head but it shows when it goes to the dyno. however, a good porting like the jobs done by the above companies have proven to increase flow without changing the port volume drastically. even then..hardly their fault for improving on an already flawed and compromised design. a 260cc intake runner is absolutely massive for the engine its on. aftermarket castings however have improved the basic design. ie: the PRC LS3 casting which not only flow more than the stock heads, they flow more with a smaller intake runner. im sure well see "crazy" things like that with the LT1.
This is stated without dealing or factoring other variables however I am only allowed to shine light so to speak. Aftermarket full headers could do major damage if not serious damage to this particular engine. My opinion would be to build onto the exhaust manifold and go back to the exhaust tips. The Cold Air Intake would only stream line the air currents and pressure waves. Wouldn't hurt anything the ECM would notice and adjust continuously as it always does. The volume of air would slightly increase entering the chambers. It would certainly pick up a few horsepower. However this engine loves E85 and the ECM itself is more than capable of bumping up the torque and horsepower through aggressive timing when it burns up E85. This ECM can tune itself that’s for certain. This is a high compression engine and it gets aggressive on e85 or mixing it with 93.
headers wont hurt/kill the engine. just like it didnt hurt/kill LS series engines. if the ecm can "auto tune" then thats even better. with a afm delete (for no other reason than the lifters are junk) and well matched cam, it really would be a monster.
The 2014 LT1 engine is simply amazing. And it has a part time smaller sister and Big Brother coming and Big Brother is downright BRUTAL in power.
we are hotrodders, stock sucks
. oem is nothing but a starting point.
Conclusion.... cold air intake YES, Full length headers? Speak to the person or company about low pressure/vacuum effect of their headers. Poorly Designed Headers Destroy ENGINES.
even a poorly designed header like the original SLP longtubes never hurt an engine, it did limit gains though.
Bigg Gunz
<snip>.
The best header/manifolds in my opinion are the LS7/LS9. Equal length and smooth exhaust pulses/air low air pressure waves, the short exhaust runners lower the EGT on all 8 cylinders. Below the manifold to the exhaust is where things can be improved. However when someone adds headers to the LS7, sure it picks up HP but the unequal length headers spikes the EGT at 1/2 -WOT due to enrichment through tuning, high lift cams rates and increase air velocity and volume. Reliability is now for certain a problem. Since all metals melt, deflect and deform under excessive hot temperatures its obvious and noted damage to the engine is 100% certain. Installing full length headers by those that say they are equal length suffer from velocity problems due to over sizing tubing which causes deceleration of the gas exiting the exhaust valves causing things heat up.
Companies like QTP, Kooks, American Racing, and others have been racing, developing, and building header systems for years. while yes, over doing it can hurt engine performance, theres plenty of information out there to show that even a 5.7LS series engine can benefit throughout the power band from a 1 7/8" diameter primary tube. without issue. if overall efficiency increases, it seems that the anecdotal evidence points to it being more beneficial than not.
This is now a compound restriction, the valves heats up, deform slightly and then let go DROPPED VALVE consequences destroying the engine. In other engines the piston with the longest exhaust runner on the header heats up and the piston expands and cracks the ring landing over time it breaks, melting, burning, holes, cracking with subjecting these cylinders to higher temperatures than other cylinders you will see failures for certain due to heat stress/unequal EGT. Catastrophic damage is certain over cumulative time.
This is because the low pressure in the exhaust system is out of sync and high temp stress the pistons, cylinder head, block...etc.... Remember Vapors and Gas likes to move from High pressure to low pressure. I will go out on a limb and say most if not ALL aftermarket headers reduce airflow through the engine resulting in some type of a heat stress condition while working the engine hard, some just perform the job better than others removing it. My opinion is spend as much time on your exhaust as you do blue printing your block and heads. What good is a powerful engine if has little or no reliability or has to be rebuilt regularly?
Dropped valves are oem's snafu, not the aftermarket mods. most dropped valves also occcur(ed) on the LS7's. if, IF headers were such a horrible addition and decreased flow and velocity, they would not see the avg gains they do across the broad rpm range. i have only seen LS series engines' pistons go when A) too much boost is applied and it buts the rings and B) the tune on tht given engine is bad. however bad tunes and the like are the risk we take as hotrodders. many MANY builds have done amazing things and are still running just fine given the doom and gloom nature of your outlook.
Air Fuel Ratio is commonly used to tune cars; you can have your PCM tuned to the perfect Air Fuel Ratio, and still run into detonation and suffer engine damage. Too much afterburning occurring on at 1/2 - WOT in the Headers. However EGT tuning is better in my expert opinion although Air Fuel Ratios should be monitored as well through a wide band.
we know. AFR is just one piece of the puzzle. egt tuning in conjunction with AFR tuning is best . however, one can reliably tune an engine without it. knowing how to tune ignition timing is an important part as it has a huge affect not only on egt but how much air fills the cylinder on the next cycle. its certainly as important as being able to tune the overall fueling of the engine. racers read plugs and log egt when possible, nothing new.
Too much air is real problem and issue when cylinder heads are ported for increase volume NOT FLOW... Velocity is everything. It’s called many things in the aftermarket but all it really is the loss ability to burn the additional volume of air and fuel and accelerating it out the exhaust cycle to the exhaust tips. This is really complicated however I will try to explain in a way that is acceptable. Accelerated air has density/mass/drag. Sitting in your home you feel nothing on your arms. Get into your car let down the window and start driving put your arm out the window and you can feel what AIR/GAS really is ...it has density you can now feel it because of the pressure is accelerated known as velocity. Too much velocity = mass/drag and this AIR/GAS becomes thick, dense, and even become lite like syrup liquid that has friction this is now viscosity. Remember as I said earlier the engine is an AIR PRESSURE SYSTEM. The trick you want to perform to gain performance is not to decelerate air density for greater ease of movement from intake to lower pressure exhaust exiting maintains the sync. The pistons convert velocity energy into pressure energy/high gas pressure and even the piston contour shape and temperature is critical. Very few people understand this too much concern is placed on compression rather than pumping the HIGH GAS out the exhaust valve.
Accelerated air velocity is valve angle (FILLED THE CYLINDER QUICKLY) and air volume/density is intake port size, shape and distances traveled. The longer the distance the more you have to take into account temperatures. Flow velocity and volume rate or obtained from vector velocity measurements along a single line of sight valve angles. Which is why in the 2014 LT1, LS7 and LS9 the valve angles are much different than the LS1, LS2, LS3.
i would be willing to bet that companies like WCCH and TEA know exactly what they are doing. however, they are working with what OEM has designed which means compromising in lots of places. yes, a bad porting job will hurt the head but it shows when it goes to the dyno. however, a good porting like the jobs done by the above companies have proven to increase flow without changing the port volume drastically. even then..hardly their fault for improving on an already flawed and compromised design. a 260cc intake runner is absolutely massive for the engine its on. aftermarket castings however have improved the basic design. ie: the PRC LS3 casting which not only flow more than the stock heads, they flow more with a smaller intake runner. im sure well see "crazy" things like that with the LT1.
This is stated without dealing or factoring other variables however I am only allowed to shine light so to speak. Aftermarket full headers could do major damage if not serious damage to this particular engine. My opinion would be to build onto the exhaust manifold and go back to the exhaust tips. The Cold Air Intake would only stream line the air currents and pressure waves. Wouldn't hurt anything the ECM would notice and adjust continuously as it always does. The volume of air would slightly increase entering the chambers. It would certainly pick up a few horsepower. However this engine loves E85 and the ECM itself is more than capable of bumping up the torque and horsepower through aggressive timing when it burns up E85. This ECM can tune itself that’s for certain. This is a high compression engine and it gets aggressive on e85 or mixing it with 93.
headers wont hurt/kill the engine. just like it didnt hurt/kill LS series engines. if the ecm can "auto tune" then thats even better. with a afm delete (for no other reason than the lifters are junk) and well matched cam, it really would be a monster.
The 2014 LT1 engine is simply amazing. And it has a part time smaller sister and Big Brother coming and Big Brother is downright BRUTAL in power.
we are hotrodders, stock sucks
. oem is nothing but a starting point.Conclusion.... cold air intake YES, Full length headers? Speak to the person or company about low pressure/vacuum effect of their headers. Poorly Designed Headers Destroy ENGINES.
even a poorly designed header like the original SLP longtubes never hurt an engine, it did limit gains though.
Bigg Gunz
engines like the LS7 have their own fatal flaws (the LS7 dropping sleeves /valves), weak rod bolts, the oiling system (which hasnt really changed with the LT1. is it really that hard to get priority main oiling in a production block?). in fact, a friend dropped a valve on a stock LS7. stock stock, no headers, cam, etc. im fairly sure the LT1 will have some issue that will pop up in time whether you think so or not.
11-26-2012 | 03:44 PM
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none of what ive said is arguing the science behind any of it, only the claims that headers are basically an engine destroying mod as well as the job head porters do with stock design head. Again, we do not like being told that anything is done for our safety. We will find a way around it and we will change things. Gm seems to be going the wrong direction concerning this. The more they help the aftermarket, the better.
Engines like the ls7 have their own fatal flaws (the ls7 dropping sleeves /valves), weak rod bolts, the oiling system (which hasnt really changed with the lt1. Is it really that hard to get priority main oiling in a production block?). In fact, a friend dropped a valve on a stock ls7. Stock stock, no headers, cam, etc. Im fairly sure the lt1 will have some issue that will pop up in time whether you think so or not.
Engines like the ls7 have their own fatal flaws (the ls7 dropping sleeves /valves), weak rod bolts, the oiling system (which hasnt really changed with the lt1. Is it really that hard to get priority main oiling in a production block?). In fact, a friend dropped a valve on a stock ls7. Stock stock, no headers, cam, etc. Im fairly sure the lt1 will have some issue that will pop up in time whether you think so or not.
pathetic your reasoning is that of a child in trouble. How about you go back to post #268 and highly your response in RED or green or some other color including that in the snip. And if you going say that someone is wrong provide your proof or knowledge behind it. I'll be sure to pass your excellence qualifications on engine development to HR HIRING MANAGERS TO REVIEW
Last edited by Bigg_Gunz; 11-26-2012 at 04:18 PM.
11-26-2012 | 07:25 PM
#268
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Thanks for the detailed answer Bigg Gunz. You're right, I was specifically asking about the ECM for the 2014 LT1, I don't know why the others are bringing up the LS motors and aftermarket. This website is built around that.
This is perhaps the most encouraging news about the new ECM...
I know there are current GM ECM's that are flex-fuel compatible using virtual sensors with complicated algorithms, but this feature is not enabled in any of the current performance vehicles. If the new LT1 is flex-fuel compatible AND picks up HP just by filling up with E85 (reminds me of the current low/high octane tables); that in itself would be ground breaking in the performance world imo. It might get lost on the masses; but the true enthusiast would certainly appreciate that.
This is perhaps the most encouraging news about the new ECM...
It would certainly pick up a few horsepower. However this engine loves E85 and the ECM itself is more than capable of bumping up the torque and horsepower through aggressive timing when it burns up E85. This ECM can tune itself that’s for certain. This is a high compression engine and it gets aggressive on e85 or mixing it with 93.
11-26-2012 | 08:57 PM
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pathetic your reasoning is that of a child in trouble. How about you go back to post #268 and highly your response in RED or green or some other color including that in the snip. And if you going say that someone is wrong provide your proof or knowledge behind it. I'll be sure to pass your excellence qualifications on engine development to HR HIRING MANAGERS TO REVIEW
youve provided hearsay that headers destroy engines. you provided your reasoning for it but havent pointed to any that have dropped valves or took out ring lands specifically because of it. its up to you to prove the claim that headers = reduced reliability and blown engine. sure, egts change with a set of headers, as do various other things. in the overblown way you are theorizing, i seriously doubt it. all we have is your word and scientifically, thats not enough. as a claimed scientist, you should know that proving a negative isnt how it works. you made the claim, its yours to prove.
11-26-2012 | 09:18 PM
#270
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He isn't saying all headers are bad. He is saying there are bad headers. And most of them are. You cant just throw some pipes together and call it done which is how MOST aftermarket headers are made. "as long as they fit" seems to be the status quo. If you knew the research that went into REAL headers I bet you would be surprised. I am happy to hear that this new ECU can self tune. The technology has been there for a while. Its about time GM used it. I'd say the tuning companies aren't too happy to hear it though.
11-26-2012 | 09:25 PM
#271
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Myself commenting on the world of OEM performance is similar to an outsider commenting on my profession. Therefore, I freely admit I speak with no authority or knowledge and just have an opinion.
If the LT1 can't be made better via the aftermarket, then I've already lost interest in the engine aside from being a curiosity. "Nice new Vette there, please enjoy watching my taillights thanks to my head/cam LSx."
I seriously doubt this will be the case. No quicker way to kill brand loyalty than eliminating aftermarket performance. Of course, the gov't regulators dont care about such things....
If the LT1 can't be made better via the aftermarket, then I've already lost interest in the engine aside from being a curiosity. "Nice new Vette there, please enjoy watching my taillights thanks to my head/cam LSx."
I seriously doubt this will be the case. No quicker way to kill brand loyalty than eliminating aftermarket performance. Of course, the gov't regulators dont care about such things....
11-26-2012 | 09:31 PM
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the snip was nothing important and was to make the 10k character cutoff. calm down and all responses are bolded.
youve provided hearsay that headers destroy engines. you provided your reasoning for it but havent pointed to any that have dropped valves or took out ring lands specifically because of it. its up to you to prove the claim that headers = reduced reliability and blown engine. sure, egts change with a set of headers, as do various other things. in the overblown way you are theorizing, i seriously doubt it. all we have is your word and scientifically, thats not enough. as a claimed scientist, you should know that proving a negative isnt how it works. you made the claim, its yours to prove.
youve provided hearsay that headers destroy engines. you provided your reasoning for it but havent pointed to any that have dropped valves or took out ring lands specifically because of it. its up to you to prove the claim that headers = reduced reliability and blown engine. sure, egts change with a set of headers, as do various other things. in the overblown way you are theorizing, i seriously doubt it. all we have is your word and scientifically, thats not enough. as a claimed scientist, you should know that proving a negative isnt how it works. you made the claim, its yours to prove.
11-26-2012 | 10:02 PM
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the snip was nothing important and was to make the 10k character cutoff. calm down and all responses are bolded.
youve provided hearsay that headers destroy engines. you provided your reasoning for it but havent pointed to any that have dropped valves or took out ring lands specifically because of it. its up to you to prove the claim that headers = reduced reliability and blown engine. sure, egts change with a set of headers, as do various other things. in the overblown way you are theorizing, i seriously doubt it. all we have is your word and scientifically, thats not enough. as a claimed scientist, you should know that proving a negative isnt how it works. you made the claim, its yours to prove.
youve provided hearsay that headers destroy engines. you provided your reasoning for it but havent pointed to any that have dropped valves or took out ring lands specifically because of it. its up to you to prove the claim that headers = reduced reliability and blown engine. sure, egts change with a set of headers, as do various other things. in the overblown way you are theorizing, i seriously doubt it. all we have is your word and scientifically, thats not enough. as a claimed scientist, you should know that proving a negative isnt how it works. you made the claim, its yours to prove.
11-26-2012 | 10:27 PM
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i was wondering this myself. most of everyone that bust ringland ive ever heard of are from boosted setups that dont address the rings and pistons on stock motors. Also, any dropped valves IVE ever heard of is from broken aftermarket springs that couldnt keep up with RPM or poor heat cycling
Dropping a valve by excessive RPM is just pure incompetence and one cannot factor in lack of common sense to correctly assembly a valve train for proper use.
BIGG GUNZ
11-26-2012 | 10:30 PM
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He isn't saying all headers are bad. He is saying there are bad headers. And most of them are. You cant just throw some pipes together and call it done which is how MOST aftermarket headers are made. "as long as they fit" seems to be the status quo. If you knew the research that went into REAL headers I bet you would be surprised. I am happy to hear that this new ECU can self tune. The technology has been there for a while. Its about time GM used it. I'd say the tuning companies aren't too happy to hear it though.
11-27-2012 | 05:01 AM
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Some really interesting stuff here (for me at least). I have enjoyed hot rodding stuff for almost 40 years. Sometimes it works well, sometimes not, but I learn stuff that's really interesting to me win or lose. So, my question is, will there be any fun factor in the new engine? Like some have said in this thread, I'm not just about laying out more bucks for the latest higher HP version of the latest ****. I get some amount of pleasure from stomping a stock LS3 car with my old (but modded) LS-1. Does this new motor have anything that I can tinker with as this IS important to me or will it be hands off and buy the newer version if you want more speed?? Having a one off is fun and chevy engines have been great for that until now.
11-27-2012 | 12:16 PM
#277
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Bigg_Gunz I see that you Choose not to answer any of the questions I posed to you previously on the ECM. So, if you can, can you please comment on those questions.
As for headers vs exhaust manifolds. Since you brought up the LS7/LS9 exhaust manifold, lets be honest. From a mnaufacturing standpoint they are impressive around the use of a hydroformed Stainless manifold. But, if you are being honest, they are a compromise on length to keep in heat energy to light off the cats to meet EPA regs. If those restrictions weren't there I don't think you can honestly tell me that a short manifold makes sense.
There is plenty of data on exhaust runner length that indicates the proper pipe size, and runner length to achieve optimal scavenging.
I do appreciate your input on engine theory but there are plenty of folks who own dynos on this site who can log Lambda, and EGT along with things like a 4 gas analyzer.
But I'm a bit confused we've had Chevrolet V8 engines since the mid 50's with all manner of intake and exhaust manifolds. Since the Gen III came out in 1997 we've had all manner of headers and intakes. No offense to the GenV, butat a VERY high level you've refined the GenIII/GenIV slightly and move from port injection to DI.
Its still fuel, and its stll getting into a cylinder and getting burned. Now, as you point out, it has to get out efficently. You made a point about some poorly designed headers getting EGT up on an LS7. Is this something you've actually tested, or is this jsut a theoretical example?
Generally
You can add timing and lower BSFC.
You can add fuel and lower BSFC.
You can add fuel and raise EGT temps.
You can take away fuel and Lower EGT temps.
I mean lets be honest every V8 Engine is a compromise unless you run a flat plane crank (which will shake you to death), or you run 8 into 1 headers, or you run crossover pipes. You still have the same 270-180-90-180-270 ad infinitum firing order.
When the exhaust valve opens, a compression wave is sent downstream and reflects back as a rarefaction wave when an opening in the exhaust system is encountered. Experimentally it has been found that the optimum position of the piston when the wave returns is ~120º. At this position the remaining exhaust gas can be scavenged from the combustion chamber. The required length of the exhaust pipe can then be determined.
When an exhaust pulse leaves the end of an exhaust pipe a shock wave travels back up the exhaust system. If the pulse arrives at the engine just as the exhaust valve starts to open, it expels the gas without using up excess energy. You can ensure that the pulse will meet the valve at exactly the right moment by calculating the exact length and diameter of the pipe required for the pulse to arrive at the valve at this optimum moment.
The stock exhaust manifolds and a LS7 or LS9 are not tuned for for those events. They are at best a "best effort" attempt to scavenge cylinders and meet EPA guidelines.
Normally the diameter of the pipe needs to be calculated so that the volume of the exhaust pipe attached to each cylinder is twice the volume of each cylinder.
So, normally you determine the capacity of your engine, by using the number of cylinders and the capacity of each. To discover the best length and diameter of pipe for your engine, you will need to know the exhaust valve timing; that is the number of degrees before bottom dead center that the valve starts to open. with this knowledge you can then set about making a tuned exhaust system by working out the following formula and applying it to your own engine:
850 (180 + N)
L = ------------- - P
RPM
where L = length of pipe in inches
N = degree before BDC exhaust valve opens
P = distance from exhaust valve to manifold
and RPM = desired RPM
When the compression wave (blowdown shock wave) reach the opened end of the pipe, it's return an expansion wave to the exhaust port.
If this expansion wave reach the opened exhaust valve just before closing (ex: crank angle > plus 10 deg), but after the intake valve opend (ex: crank angle > minus 5 deg), and the effective cylinder volme is small (near TDC), the expansion wave will flow through the intake port upto the intake atmosphere increasing the aspiration.
As an example, the exhaust pipe lenght, in degree, is [ (40+180+10) / 2 ] 115 degrees (divided by two because back & forth travel) at the maximum targeted RPM and Exhaust Gaz Temperature, Tk, (in kelvin).
Always in the example, the intake pipe lenght, in degree, is [ (5+180+45) / 2 ] 115 degrees (divided by two because back & forth travel) at the maximum targeted RPM and Intake Gaz Temperature, Tk, (in kelvin).
Consider the wave speed, Ws, formula as [ Ws = sqrt( Gg * Ry * Tk ) ], where Ge is the "specific heat ratio" for exhaust or intake gaz, and Ry is the "ideal gaz constant". By use, the maximum targeted RPM is the RPM where you actually reach the maximum HP.
At a lower RPM than the maximum targeted RPM, the expansion wave will reach the exhaust port before the exhaust valve close, and may be before the intake valve open, therefore, causing suction into the cylinder chamber (that is normally very good).
But, from what I take from what you are saying, you are saying its bad and leads to High EGT, and dropped valves.
So, let me go back to what I said before. The LT motor is an incremental improvement on the LS family. LS motors run fine with headers (even poorly designed ones). The LT has moved from Port injection to DI. Again, we've been tuning with DI motors for a few years now. Nothing magic there either.
If the computer is as powerful as you allude to I guess the question is if it has enough headroom to account for changes to the overall system and self tune so that it does not need aftermarket tuning help. After all the only reason any of us has to tune is because once you take the computer out of its availiable parameters it doesn't know what to do.
If you look at the tuning most of us do its simply to get the computer back into a window where it can operate as intended.
Now, I will say that GM intentionally removes power from the ECM to help keep the driveline alive and thus that 100K mile powetrain warranty. Things like PE enrichment delay, and huge "holes" in the timing curve to drop power. You can't argue those are anything but GM taking power out of vehicles.
You can argue all you want about voiding EPA certification, but I think you recognize that optimziing the intake and exahaut tract of the vehicle throws the computer off,and you have to tue the car to get it back to the correct A/F. So, leaving it un-tuned will actually damage the catalytic converters and has the car polluting more than if it were tuned. I understand your argument, I've seen it before, but it does not stand up to the sniff test.
Look I understand if GM doesn't want people poking arond in the ECM and are worried about what people will do to their own cars. I think the past 15 years has shown that people are pretty capable.
I just don't accept tha tthe LT motor is so fragile that it can't take a set of headers (good or bad) without destroying itself, and reasons like that are a justification around locking the ECM. I get it if GM wants to keep folks out of ECM's to reduce warranty claims on the powertrain. But just be honest about it.
Also, as was pointed out here earlier. There are plenty of ways to crack systems virtual or physical. Where there is a will there is a way....
As for headers vs exhaust manifolds. Since you brought up the LS7/LS9 exhaust manifold, lets be honest. From a mnaufacturing standpoint they are impressive around the use of a hydroformed Stainless manifold. But, if you are being honest, they are a compromise on length to keep in heat energy to light off the cats to meet EPA regs. If those restrictions weren't there I don't think you can honestly tell me that a short manifold makes sense.
There is plenty of data on exhaust runner length that indicates the proper pipe size, and runner length to achieve optimal scavenging.
I do appreciate your input on engine theory but there are plenty of folks who own dynos on this site who can log Lambda, and EGT along with things like a 4 gas analyzer.
But I'm a bit confused we've had Chevrolet V8 engines since the mid 50's with all manner of intake and exhaust manifolds. Since the Gen III came out in 1997 we've had all manner of headers and intakes. No offense to the GenV, butat a VERY high level you've refined the GenIII/GenIV slightly and move from port injection to DI.
Its still fuel, and its stll getting into a cylinder and getting burned. Now, as you point out, it has to get out efficently. You made a point about some poorly designed headers getting EGT up on an LS7. Is this something you've actually tested, or is this jsut a theoretical example?
Generally
You can add timing and lower BSFC.
You can add fuel and lower BSFC.
You can add fuel and raise EGT temps.
You can take away fuel and Lower EGT temps.
I mean lets be honest every V8 Engine is a compromise unless you run a flat plane crank (which will shake you to death), or you run 8 into 1 headers, or you run crossover pipes. You still have the same 270-180-90-180-270 ad infinitum firing order.
When the exhaust valve opens, a compression wave is sent downstream and reflects back as a rarefaction wave when an opening in the exhaust system is encountered. Experimentally it has been found that the optimum position of the piston when the wave returns is ~120º. At this position the remaining exhaust gas can be scavenged from the combustion chamber. The required length of the exhaust pipe can then be determined.
When an exhaust pulse leaves the end of an exhaust pipe a shock wave travels back up the exhaust system. If the pulse arrives at the engine just as the exhaust valve starts to open, it expels the gas without using up excess energy. You can ensure that the pulse will meet the valve at exactly the right moment by calculating the exact length and diameter of the pipe required for the pulse to arrive at the valve at this optimum moment.
The stock exhaust manifolds and a LS7 or LS9 are not tuned for for those events. They are at best a "best effort" attempt to scavenge cylinders and meet EPA guidelines.
Normally the diameter of the pipe needs to be calculated so that the volume of the exhaust pipe attached to each cylinder is twice the volume of each cylinder.
So, normally you determine the capacity of your engine, by using the number of cylinders and the capacity of each. To discover the best length and diameter of pipe for your engine, you will need to know the exhaust valve timing; that is the number of degrees before bottom dead center that the valve starts to open. with this knowledge you can then set about making a tuned exhaust system by working out the following formula and applying it to your own engine:
850 (180 + N)
L = ------------- - P
RPM
where L = length of pipe in inches
N = degree before BDC exhaust valve opens
P = distance from exhaust valve to manifold
and RPM = desired RPM
When the compression wave (blowdown shock wave) reach the opened end of the pipe, it's return an expansion wave to the exhaust port.
If this expansion wave reach the opened exhaust valve just before closing (ex: crank angle > plus 10 deg), but after the intake valve opend (ex: crank angle > minus 5 deg), and the effective cylinder volme is small (near TDC), the expansion wave will flow through the intake port upto the intake atmosphere increasing the aspiration.
As an example, the exhaust pipe lenght, in degree, is [ (40+180+10) / 2 ] 115 degrees (divided by two because back & forth travel) at the maximum targeted RPM and Exhaust Gaz Temperature, Tk, (in kelvin).
Always in the example, the intake pipe lenght, in degree, is [ (5+180+45) / 2 ] 115 degrees (divided by two because back & forth travel) at the maximum targeted RPM and Intake Gaz Temperature, Tk, (in kelvin).
Consider the wave speed, Ws, formula as [ Ws = sqrt( Gg * Ry * Tk ) ], where Ge is the "specific heat ratio" for exhaust or intake gaz, and Ry is the "ideal gaz constant". By use, the maximum targeted RPM is the RPM where you actually reach the maximum HP.
At a lower RPM than the maximum targeted RPM, the expansion wave will reach the exhaust port before the exhaust valve close, and may be before the intake valve open, therefore, causing suction into the cylinder chamber (that is normally very good).
But, from what I take from what you are saying, you are saying its bad and leads to High EGT, and dropped valves.
So, let me go back to what I said before. The LT motor is an incremental improvement on the LS family. LS motors run fine with headers (even poorly designed ones). The LT has moved from Port injection to DI. Again, we've been tuning with DI motors for a few years now. Nothing magic there either.
If the computer is as powerful as you allude to I guess the question is if it has enough headroom to account for changes to the overall system and self tune so that it does not need aftermarket tuning help. After all the only reason any of us has to tune is because once you take the computer out of its availiable parameters it doesn't know what to do.
If you look at the tuning most of us do its simply to get the computer back into a window where it can operate as intended.
Now, I will say that GM intentionally removes power from the ECM to help keep the driveline alive and thus that 100K mile powetrain warranty. Things like PE enrichment delay, and huge "holes" in the timing curve to drop power. You can't argue those are anything but GM taking power out of vehicles.
You can argue all you want about voiding EPA certification, but I think you recognize that optimziing the intake and exahaut tract of the vehicle throws the computer off,and you have to tue the car to get it back to the correct A/F. So, leaving it un-tuned will actually damage the catalytic converters and has the car polluting more than if it were tuned. I understand your argument, I've seen it before, but it does not stand up to the sniff test.
Look I understand if GM doesn't want people poking arond in the ECM and are worried about what people will do to their own cars. I think the past 15 years has shown that people are pretty capable.
I just don't accept tha tthe LT motor is so fragile that it can't take a set of headers (good or bad) without destroying itself, and reasons like that are a justification around locking the ECM. I get it if GM wants to keep folks out of ECM's to reduce warranty claims on the powertrain. But just be honest about it.
Also, as was pointed out here earlier. There are plenty of ways to crack systems virtual or physical. Where there is a will there is a way....
11-27-2012 | 01:10 PM
#278
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If you have a problem with hearing the "TRUTH" then look away now....Seriously.
I know many of YOU.... Not all but many prefer to take the easy way out and "SHOOT" the messenger. That's fine with me honestly I have no problem being your target. The anger is just a way of saying I don't understand but I still care. And we don't take it personal we are solutionist. We actually care about what you have to say. There are many engineers and developers, research firms from all BIG 3 and countless others within this site watching... reading, understanding, listening, and brainstorming. Many are silent; most don't have login accounts but track important issues for future improvements. This site is an invaluable tool to amateurs, intermediates and experts alike feel. Feel Grateful they are not charging for access to the data within it. It is valuable I am one that will say to LS1Tech.com and those respectful users with dignity that are within it thank you. You guys and your love of power inspire our action to develop things.
Now like a fall from a high building...gravity is a force and the fall to the truth is going HURT.
Many of you complain about factors and features you don't understand, it’s not that your are wrong it’s just that you don’t have the knowledge to understand what is happening. Engines are extremely complicated. Nothing is simple when it comes to engine. Thousands of variables must work in sync or failure is certain. When you get into performance that person up the risk by a factor of three. "CLOSE ENOUGH, IS NOT GOOD ENOUGH." It has to be RIGHT each and every time!!
We over engineer our engines from a structure factor on purpose. We intentionally leave performance on the table for you Horse Power Junkies. And you wonder why certain ad on's changes can give you significant gains in HP/TQ. This is no mistake this is intentional believe it or not. And we will continue to do so...our bread and butter are both aftermarket and OEM.
Many of you don't have the dignity to say, "When you made a mistake and damaged your engine" that is was your inexperience as making those part upgrades function as a system. You would rather blame the engine builder or Aftermarket part supplier for your mistake. And give them grief and bad mouth their aftermarket parts that are extremely tough and durable when installed correctly in which the matter it was designed.
Oh yes the blame game is LONG and INTENESE your hard earned money is at stake and you just want your engine run doesn't matter if it runs 10,000 miles or less you just want to kick tires and show EGO's.
And some of you take pride is ripping off these After Market suppliers getting replacement parts for free even though it was your lack of competence to ensure all other recommended upgrades were done as well. Or you decided to risk 1,000's to save a few hundreds and do it yourself or have your buddy from the street install something he isn't qualified to do. Pathetic.... Going fast is a system and the system is not something you CHEAT or make CHEAP.
So stop it... aftermarket suppliers & OEM engineers know when you're lying about the cause of a part failure. Whether it’s Turbos, Crankshafts, Rods, Pistons, Heads, Etc... They engineered it and designed they know what it takes to make it fail. The business model is test test and test until it has catastrophic failure. Then break it again and again. Only then is it ready for the customer. Really all that is needed is the part itself after failure to realize what exactly happen usually with 15minutes or less. Customers have the ability to lie. The now...failed part doesn't lie...it tells the story in which it really happen. Metal isn't bias or loyal to either the supplier or customers. Think about that next time you before you tell someone a lie about what happen.
When the aftermarket part supplier calls you out on your bullshit story. And refuse to cover the cost for your mistake. Then its run to the internet and blog about how terrible your experience was...when the truth of the matter is your story flew about as far as a concrete Frisbee. It's like a child lying to your face about pooping their pamper and you can just smell the ****. Yet they continue to lie, rather than say "help" me wipe my *** and start over with a clean pamper and until I can learn to use the toilet. Your pride isn't as important as learning. Get out of hot rodding if you don't understand what was just said, you're making it messy for those that are true performance gear heads and enjoy going fast. You're driving up the cost of everything and effecting families.
Just have respect for the hobby and bow out with grace. Do run to second base and then blame the engine builder. Oh..."NO" the engine wasn't set up correctly or assembled wrong. Quality engine builders deserve the most respect. The TRUTH of the matter is any ENGINE any size...wants to tear itself apart when running. It is up to the Engine Builder to Balance this act of wanting self destruct. Next time you see a quality engine builder shake his hands....why? Because that guy is balancing an Elephant on the sharp end of a razor blade. If you truly understood the dynamics of it and tolerances you would kiss these great guys feet. "CLOSE ENOUGH ISN"T GOOD ENOUGH," Engine builders have ZERO room for error understand... "ZERO!" When they say do something.... do it. These guys are detectives and magicians. They will give you the magic you want, which is horsepower or they will become detectives to figure what happen when you cheap out or cheat the system of dynamic cylinder pressures and destroy your engine. Remember Engine building takes time no two engines are the same. Different sizes, millions of combinations Different parts, Different usages and environments. Give them time to calculate what is best for you. You can't cheat math or geometry. It's all math and thermodynamics okay? How many engine stands with 450lbs paper weights have you seen? Or take a trip to your local machine shop a lot are just laying around I'm sure.
I know many of YOU.... Not all but many prefer to take the easy way out and "SHOOT" the messenger. That's fine with me honestly I have no problem being your target. The anger is just a way of saying I don't understand but I still care. And we don't take it personal we are solutionist. We actually care about what you have to say. There are many engineers and developers, research firms from all BIG 3 and countless others within this site watching... reading, understanding, listening, and brainstorming. Many are silent; most don't have login accounts but track important issues for future improvements. This site is an invaluable tool to amateurs, intermediates and experts alike feel. Feel Grateful they are not charging for access to the data within it. It is valuable I am one that will say to LS1Tech.com and those respectful users with dignity that are within it thank you. You guys and your love of power inspire our action to develop things.
Now like a fall from a high building...gravity is a force and the fall to the truth is going HURT.
Many of you complain about factors and features you don't understand, it’s not that your are wrong it’s just that you don’t have the knowledge to understand what is happening. Engines are extremely complicated. Nothing is simple when it comes to engine. Thousands of variables must work in sync or failure is certain. When you get into performance that person up the risk by a factor of three. "CLOSE ENOUGH, IS NOT GOOD ENOUGH." It has to be RIGHT each and every time!!
We over engineer our engines from a structure factor on purpose. We intentionally leave performance on the table for you Horse Power Junkies. And you wonder why certain ad on's changes can give you significant gains in HP/TQ. This is no mistake this is intentional believe it or not. And we will continue to do so...our bread and butter are both aftermarket and OEM.
Many of you don't have the dignity to say, "When you made a mistake and damaged your engine" that is was your inexperience as making those part upgrades function as a system. You would rather blame the engine builder or Aftermarket part supplier for your mistake. And give them grief and bad mouth their aftermarket parts that are extremely tough and durable when installed correctly in which the matter it was designed.
Oh yes the blame game is LONG and INTENESE your hard earned money is at stake and you just want your engine run doesn't matter if it runs 10,000 miles or less you just want to kick tires and show EGO's.
And some of you take pride is ripping off these After Market suppliers getting replacement parts for free even though it was your lack of competence to ensure all other recommended upgrades were done as well. Or you decided to risk 1,000's to save a few hundreds and do it yourself or have your buddy from the street install something he isn't qualified to do. Pathetic.... Going fast is a system and the system is not something you CHEAT or make CHEAP.
So stop it... aftermarket suppliers & OEM engineers know when you're lying about the cause of a part failure. Whether it’s Turbos, Crankshafts, Rods, Pistons, Heads, Etc... They engineered it and designed they know what it takes to make it fail. The business model is test test and test until it has catastrophic failure. Then break it again and again. Only then is it ready for the customer. Really all that is needed is the part itself after failure to realize what exactly happen usually with 15minutes or less. Customers have the ability to lie. The now...failed part doesn't lie...it tells the story in which it really happen. Metal isn't bias or loyal to either the supplier or customers. Think about that next time you before you tell someone a lie about what happen.
When the aftermarket part supplier calls you out on your bullshit story. And refuse to cover the cost for your mistake. Then its run to the internet and blog about how terrible your experience was...when the truth of the matter is your story flew about as far as a concrete Frisbee. It's like a child lying to your face about pooping their pamper and you can just smell the ****. Yet they continue to lie, rather than say "help" me wipe my *** and start over with a clean pamper and until I can learn to use the toilet. Your pride isn't as important as learning. Get out of hot rodding if you don't understand what was just said, you're making it messy for those that are true performance gear heads and enjoy going fast. You're driving up the cost of everything and effecting families.
Just have respect for the hobby and bow out with grace. Do run to second base and then blame the engine builder. Oh..."NO" the engine wasn't set up correctly or assembled wrong. Quality engine builders deserve the most respect. The TRUTH of the matter is any ENGINE any size...wants to tear itself apart when running. It is up to the Engine Builder to Balance this act of wanting self destruct. Next time you see a quality engine builder shake his hands....why? Because that guy is balancing an Elephant on the sharp end of a razor blade. If you truly understood the dynamics of it and tolerances you would kiss these great guys feet. "CLOSE ENOUGH ISN"T GOOD ENOUGH," Engine builders have ZERO room for error understand... "ZERO!" When they say do something.... do it. These guys are detectives and magicians. They will give you the magic you want, which is horsepower or they will become detectives to figure what happen when you cheap out or cheat the system of dynamic cylinder pressures and destroy your engine. Remember Engine building takes time no two engines are the same. Different sizes, millions of combinations Different parts, Different usages and environments. Give them time to calculate what is best for you. You can't cheat math or geometry. It's all math and thermodynamics okay? How many engine stands with 450lbs paper weights have you seen? Or take a trip to your local machine shop a lot are just laying around I'm sure.
11-27-2012 | 01:11 PM
#279
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Which brings me to my next topic... engines evolves.... stay current or bow out gracefully.
Carbs -----> Fuel Injections -----> Direct Injections -----> VVT ------- VVT + Direct Injections.
The principles are the same of a engine, however...today’s engines aren't for those without understanding of technology. Any tuner or tuning company with pride will tell you....Tuning today’s engines is difficult and complex. Throw in VVT alone..... And most will give up and resort to what is safe for their skill level. Which convert your engine back to non-vvt standards for performance gains? SAD BUT TRUE.... The aftermarket hasn't mastered VVT and VVT is simple when you understand what is happening. Direct Injection is DOWN RIGHT the most complicated process ever in cars. And that is no stretch of the truth. That is a Fact...
If you are looking to make some serious money.... go back to school or a school program provided by Aftermarket Company developing tuning for direct injection. Direct Injection isn't going away it....... is the way. You don't need to become an engineer in combustion like myself.
BIG 3 are moving into more and more powerful engines. The best is yet to come... and returning these engines back to non-VVT or Non Direct Injections isn't an option. You can either adapt or play with establish platforms that lack these advanced power capabilities.
However more than likely someone with enough determination or drive domestically and abroad will go to school and develop the understanding and learning curve of Direct Injection combustion and become extremely wealthy in the aftermarket. Until these...we have fail safes in place to keep you from turning a 450lbs engine into a paperweight. Master the LY6 VVT first.... so far NO ONE has.... And we are 100% sure no one has... this engine is begging for 2 developments in the aftermarket to reach 650hp in N/A form and maintains reliable performance. However that is as far as I will go on that topic.
The 2014 LT1 platform will be the best V8 engine of all times in my opinion. Like a disrespectful red head step child the 2014 LT1 lays the smack down on the LS3, LS7 and LSA. There are no comparisons or equals to this engine capabilities. It's not what you think or feel and complain about on here. It is what we know. No mixing of air and fuel in the intake port. You can rejoice, the fuel is cooler now thanks to this and gets directly into the hot combustion chamber. Thermodynamics for the K.O!! The engine runs a higher ignition timing the compression is way up and without engine detonation or knock. The cooler fuel cools down the incoming air charge for a similar effect as a dry shot of nitrous. The engine doesn't lean out thanks to the awesome increase airflow of the heads. The pocket of air is swirling in chamber thanks to those special contoured pistons, which this vortex of air insulates the burning mix from the piston and cylinder walls, which means more heat goes into the combustion cycle event itself which means the hotter the flame the more efficient it is at creating Dynamic Cylinder Pressure which is Horsepower! This engine will shock you in finally output numbers! And the Bigger Brother engine is coming and it is like an IRON FIST TO THE FACE!
Summary for those Forrest Gump’s that will draw the wrong conclusion.
1. be humble when you make mistakes. And Ask for help from qualified people or businesses.
2. FUEL TABLES ARE OFF LIMITS!
3. Give feed back to the aftermarket suppliers/vendors on performance.
4. Calm down Performance isn't dead or dying.
5. Close is not good enough...do it right if you going to do it.
Bigg Gunz
Carbs -----> Fuel Injections -----> Direct Injections -----> VVT ------- VVT + Direct Injections.
The principles are the same of a engine, however...today’s engines aren't for those without understanding of technology. Any tuner or tuning company with pride will tell you....Tuning today’s engines is difficult and complex. Throw in VVT alone..... And most will give up and resort to what is safe for their skill level. Which convert your engine back to non-vvt standards for performance gains? SAD BUT TRUE.... The aftermarket hasn't mastered VVT and VVT is simple when you understand what is happening. Direct Injection is DOWN RIGHT the most complicated process ever in cars. And that is no stretch of the truth. That is a Fact...
If you are looking to make some serious money.... go back to school or a school program provided by Aftermarket Company developing tuning for direct injection. Direct Injection isn't going away it....... is the way. You don't need to become an engineer in combustion like myself.
BIG 3 are moving into more and more powerful engines. The best is yet to come... and returning these engines back to non-VVT or Non Direct Injections isn't an option. You can either adapt or play with establish platforms that lack these advanced power capabilities.
However more than likely someone with enough determination or drive domestically and abroad will go to school and develop the understanding and learning curve of Direct Injection combustion and become extremely wealthy in the aftermarket. Until these...we have fail safes in place to keep you from turning a 450lbs engine into a paperweight. Master the LY6 VVT first.... so far NO ONE has.... And we are 100% sure no one has... this engine is begging for 2 developments in the aftermarket to reach 650hp in N/A form and maintains reliable performance. However that is as far as I will go on that topic.
The 2014 LT1 platform will be the best V8 engine of all times in my opinion. Like a disrespectful red head step child the 2014 LT1 lays the smack down on the LS3, LS7 and LSA. There are no comparisons or equals to this engine capabilities. It's not what you think or feel and complain about on here. It is what we know. No mixing of air and fuel in the intake port. You can rejoice, the fuel is cooler now thanks to this and gets directly into the hot combustion chamber. Thermodynamics for the K.O!! The engine runs a higher ignition timing the compression is way up and without engine detonation or knock. The cooler fuel cools down the incoming air charge for a similar effect as a dry shot of nitrous. The engine doesn't lean out thanks to the awesome increase airflow of the heads. The pocket of air is swirling in chamber thanks to those special contoured pistons, which this vortex of air insulates the burning mix from the piston and cylinder walls, which means more heat goes into the combustion cycle event itself which means the hotter the flame the more efficient it is at creating Dynamic Cylinder Pressure which is Horsepower! This engine will shock you in finally output numbers! And the Bigger Brother engine is coming and it is like an IRON FIST TO THE FACE!
Summary for those Forrest Gump’s that will draw the wrong conclusion.
1. be humble when you make mistakes. And Ask for help from qualified people or businesses.
2. FUEL TABLES ARE OFF LIMITS!
3. Give feed back to the aftermarket suppliers/vendors on performance.
4. Calm down Performance isn't dead or dying.
5. Close is not good enough...do it right if you going to do it.
Bigg Gunz
11-27-2012 | 01:34 PM
#280
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J-Rod
Since you're playing or pretending your qualified lets establish that you know 1% of what you are copying and pasting from GOOGLE.
Here is an equation I want you to figure out..... really simple...so follow along....you have an exhaust valve 1.60 in size. And lets say that area under the valve seat region is 75% of the valve head with a .8 square inch area. if that is the smallest cross section are in the exhaust path what is the choke point hold value?
Next lets that the header primary is 1 7/8 O.D and 1 5.8 I.D When the velocity from the combustion cycle is completed and pases from the .8 square inch area to an area of 1 5/8 I.D x 1 7/8 O.D The velocity drops from ?????? ft/sec to ????ft/sec. Which then passes into a 3" collector sector (7.2 in sq area) airflows drop to ?????Ft/sec And here's a variable I shouldn't give you but I know your bluffing so here is the exhaust cycles... is 70 per second.... So tell me what is the missing variables and exhaust pressures at the collector ....and this is very very easy.... for someone that is talking to me about "tuned exhaust evacuation values"...... I'll wait as long as it takes for you to reply.... with the answers... although it shouldn't take more than 4 minutes.
warmest regards.
Bigg Gunz...
Since you're playing or pretending your qualified lets establish that you know 1% of what you are copying and pasting from GOOGLE.
Here is an equation I want you to figure out..... really simple...so follow along....you have an exhaust valve 1.60 in size. And lets say that area under the valve seat region is 75% of the valve head with a .8 square inch area. if that is the smallest cross section are in the exhaust path what is the choke point hold value?
Next lets that the header primary is 1 7/8 O.D and 1 5.8 I.D When the velocity from the combustion cycle is completed and pases from the .8 square inch area to an area of 1 5/8 I.D x 1 7/8 O.D The velocity drops from ?????? ft/sec to ????ft/sec. Which then passes into a 3" collector sector (7.2 in sq area) airflows drop to ?????Ft/sec And here's a variable I shouldn't give you but I know your bluffing so here is the exhaust cycles... is 70 per second.... So tell me what is the missing variables and exhaust pressures at the collector ....and this is very very easy.... for someone that is talking to me about "tuned exhaust evacuation values"...... I'll wait as long as it takes for you to reply.... with the answers... although it shouldn't take more than 4 minutes.
warmest regards.
Bigg Gunz...