Cylinder head gurus (and salesman) join us!
09-14-2018, 08:19 PM
#81
ModSquad
iTrader: (6)
Kent, they had to spin the blower faster to get the boost back to where it was with the more restrictive heads. To me it shows all the more how the heads helped out. You have to compare both setups at the same boost level, or it’s not a true apples to apples comparison.
09-14-2018, 10:24 PM
#82
KCS, your definitely one of the most knowledgeable folks on engine builds on the forum and I respect your knowledge, so let ask if that makes sense.
My understanding is air flow restriction was greatly reduced when the heads were swapped. Boost is in many ways a measure of restriction. With more air going into the motor with far less resistance due to the ported heads, the boost level naturally has to drop at the same blower rpm. This is proof the ported heads flow more air. Now to make the test apples to apples the blower speed has to be increased to reach the same level of boost. In other words the level of of restriction has to be measured at the same boost value. When that is done the dyno show about a 100 wtq gain and 100 whp gain.
Turning the blower more rpm is analogous in a way to turning a motor more rpm after a cam swap. If we switch the stock cam in an 02 Z28 that made peak hp at ~5,400 rpm to a MS3 magic stick that peaks at ~6,500 rpm. We turn the motor more rpm and compare the whole power curves and peak values. We don't just limit looking at the dyno graph to the hp & tq value at 5,400 rpm.
My view of the question at hand...
As to whether that's proof quality ported heads are worth the cost is buyer dependant. Cost per whp, IfTony's heads cost $3,000 decked out for a boosted application that's $30 a whp and wtq. If I could budget a blower build, I would definitely want a set of Tony's heads or a set of BTR/TEA worked Trick Flow's for my blower.
Seems a better value to me for hp/$ value than a Fast 102 LSXR intake $850 NW 102 $389 TB , Fast fuel rails $200, use same injectors etc that costs ~$1,439 that yields a ~30 hp gain in an application which is about $48 per hp. Clearly the Fast upgrade is very popular and normally viewed as cost effective and worthwhile. I felt like it was for my 416.
My understanding is air flow restriction was greatly reduced when the heads were swapped. Boost is in many ways a measure of restriction. With more air going into the motor with far less resistance due to the ported heads, the boost level naturally has to drop at the same blower rpm. This is proof the ported heads flow more air. Now to make the test apples to apples the blower speed has to be increased to reach the same level of boost. In other words the level of of restriction has to be measured at the same boost value. When that is done the dyno show about a 100 wtq gain and 100 whp gain.
Turning the blower more rpm is analogous in a way to turning a motor more rpm after a cam swap. If we switch the stock cam in an 02 Z28 that made peak hp at ~5,400 rpm to a MS3 magic stick that peaks at ~6,500 rpm. We turn the motor more rpm and compare the whole power curves and peak values. We don't just limit looking at the dyno graph to the hp & tq value at 5,400 rpm.
My view of the question at hand...
As to whether that's proof quality ported heads are worth the cost is buyer dependant. Cost per whp, IfTony's heads cost $3,000 decked out for a boosted application that's $30 a whp and wtq. If I could budget a blower build, I would definitely want a set of Tony's heads or a set of BTR/TEA worked Trick Flow's for my blower.
Seems a better value to me for hp/$ value than a Fast 102 LSXR intake $850 NW 102 $389 TB , Fast fuel rails $200, use same injectors etc that costs ~$1,439 that yields a ~30 hp gain in an application which is about $48 per hp. Clearly the Fast upgrade is very popular and normally viewed as cost effective and worthwhile. I felt like it was for my 416.
09-15-2018, 09:27 AM
#83
ModSquad
iTrader: (6)
KCS, your definitely one of the most knowledgeable folks on engine builds on the forum and I respect your knowledge, so let ask if that makes sense.
My understanding is air flow restriction was greatly reduced when the heads were swapped. Boost is in many ways a measure of restriction. With more air going into the motor with far less resistance due to the ported heads, the boost level naturally has to drop at the same blower rpm. This is proof the ported heads flow more air. Now to make the test apples to apples the blower speed has to be increased to reach the same level of boost. In other words the level of of restriction has to be measured at the same boost value. When that is done the dyno show about a 100 wtq gain and 100 whp gain.
Turning the blower more rpm is analogous in a way to turning a motor more rpm after a cam swap. If we switch the stock cam in an 02 Z28 that made peak hp at ~5,400 rpm to a MS3 magic stick that peaks at ~6,500 rpm. We turn the motor more rpm and compare the whole power curves and peak values. We don't just limit looking at the dyno graph to the hp & tq value at 5,400 rpm.
My view of the question at hand...
As to whether that's proof quality ported heads are worth the cost is buyer dependant. Cost per whp, IfTony's heads cost $3,000 decked out for a boosted application that's $30 a whp and wtq. If I could budget a blower build, I would definitely want a set of Tony's heads or a set of BTR/TEA worked Trick Flow's for my blower.
Seems a better value to me for hp/$ value than a Fast 102 LSXR intake $850 NW 102 $389 TB , Fast fuel rails $200, use same injectors etc that costs ~$1,439 that yields a ~30 hp gain in an application which is about $48 per hp. Clearly the Fast upgrade is very popular and normally viewed as cost effective and worthwhile. I felt like it was for my 416.
My understanding is air flow restriction was greatly reduced when the heads were swapped. Boost is in many ways a measure of restriction. With more air going into the motor with far less resistance due to the ported heads, the boost level naturally has to drop at the same blower rpm. This is proof the ported heads flow more air. Now to make the test apples to apples the blower speed has to be increased to reach the same level of boost. In other words the level of of restriction has to be measured at the same boost value. When that is done the dyno show about a 100 wtq gain and 100 whp gain.
Turning the blower more rpm is analogous in a way to turning a motor more rpm after a cam swap. If we switch the stock cam in an 02 Z28 that made peak hp at ~5,400 rpm to a MS3 magic stick that peaks at ~6,500 rpm. We turn the motor more rpm and compare the whole power curves and peak values. We don't just limit looking at the dyno graph to the hp & tq value at 5,400 rpm.
My view of the question at hand...
As to whether that's proof quality ported heads are worth the cost is buyer dependant. Cost per whp, IfTony's heads cost $3,000 decked out for a boosted application that's $30 a whp and wtq. If I could budget a blower build, I would definitely want a set of Tony's heads or a set of BTR/TEA worked Trick Flow's for my blower.
Seems a better value to me for hp/$ value than a Fast 102 LSXR intake $850 NW 102 $389 TB , Fast fuel rails $200, use same injectors etc that costs ~$1,439 that yields a ~30 hp gain in an application which is about $48 per hp. Clearly the Fast upgrade is very popular and normally viewed as cost effective and worthwhile. I felt like it was for my 416.
09-15-2018, 09:39 AM
#85
ModSquad
iTrader: (6)
09-15-2018, 01:34 PM
#87
ModSquad
iTrader: (6)
09-15-2018, 02:22 PM
#88
TECH Addict
Hmm,, so no matter what you do to an engine,, for N/A vacuum is limited to about 15" ,, Flip to F/I and pressurization is only limited by the compressor. You get efficiency with a better path for the air , which to a certain extent can be offset by bigger compressor.
There are limits in certain conditions that will stop air flow whether N/A or F/I. Example: I worked with a college team on a SAE formula car, one of the requirements was a specific air box with a restrictor plate. What the students learned was that with a thin plate, air flow dropped by 30% when the air moving though the hole reached the speed of sound at the given pressure it was operating at. Basically there was a sonic boom that became continuous at the restrictor plate, under vacume there was no way to get around it, under pressure you could brute force your way past it,,, BUT it took an extreme amount of pressure, and when the wave broke over you got a huge pressure surge down stream of the restrictor which was reflected by a huge drop in pressure upstream, to prevent some wild fluid behavior of the air you had to boost past the fallover and totally manage the pressure after the plate. In the end what they learned is a restrictor plate is a very effective way to make engines equal, because power is the result of the number of Pounds of Air and fuel your mixing no matter what the delivery method.. So they focused on making their car lighter, and they made sure two of their crew really knew how to drive a road race course. One of the students went on to develop suspension at Rouche, Based on their cars performance in the SAE events..
I only used this example to show that in that air flow path there is a lot going on, and each strategy has a finite effect on the outcome..
I built a turbo SR4Ti a few years back (Ford 2.3) , with a stock head and upgraded turbo it made about 350 on the engine dyno, with a high end professionally cast and ported head it did 555.. all other parts remained the same except for the tune to adjust for the new air flow... The head cost about 8 grand as I recall..
There are limits in certain conditions that will stop air flow whether N/A or F/I. Example: I worked with a college team on a SAE formula car, one of the requirements was a specific air box with a restrictor plate. What the students learned was that with a thin plate, air flow dropped by 30% when the air moving though the hole reached the speed of sound at the given pressure it was operating at. Basically there was a sonic boom that became continuous at the restrictor plate, under vacume there was no way to get around it, under pressure you could brute force your way past it,,, BUT it took an extreme amount of pressure, and when the wave broke over you got a huge pressure surge down stream of the restrictor which was reflected by a huge drop in pressure upstream, to prevent some wild fluid behavior of the air you had to boost past the fallover and totally manage the pressure after the plate. In the end what they learned is a restrictor plate is a very effective way to make engines equal, because power is the result of the number of Pounds of Air and fuel your mixing no matter what the delivery method.. So they focused on making their car lighter, and they made sure two of their crew really knew how to drive a road race course. One of the students went on to develop suspension at Rouche, Based on their cars performance in the SAE events..
I only used this example to show that in that air flow path there is a lot going on, and each strategy has a finite effect on the outcome..
I built a turbo SR4Ti a few years back (Ford 2.3) , with a stock head and upgraded turbo it made about 350 on the engine dyno, with a high end professionally cast and ported head it did 555.. all other parts remained the same except for the tune to adjust for the new air flow... The head cost about 8 grand as I recall..
09-16-2018, 03:56 PM
#89
10 Second Club
Kent, they had to spin the blower faster to get the boost back to where it was with the more restrictive heads. To me it shows all the more how the heads helped out. You have to compare both setups at the same boost level, or it’s not a true apples to apples comparison.
09-17-2018, 01:57 PM
#93
Here is quote from Darin Morgan:
"The chamber design and camshaft exhaust duration are two huge factors for both supercharged and Nitrous engines. They are basically the exact opposite of what you would do for an NA engine. In an NA engine the quench/squish area is overwhelmingly important. In a supercharged or nitrous engine its important to get rid of all the squish quench area. The pressure rise and flame travel is so fast they a high squish chamber will end gas detonate even though the squish quench is trying to cool the mixture.
If you design a port for an NA engine that's what works best in both Nitrous and supercharged engines. Some people mistakenly try and make them bigger and the engine never responds properly when you do this. I have done some pretty extensive R&D with supercharged stuff in the last 8 years and have tried many different port designs. I of course tried to get fancy and calculate how much bigger the port "should" be and every single time I enlarged it, the engine lost power". end quote
"The chamber design and camshaft exhaust duration are two huge factors for both supercharged and Nitrous engines. They are basically the exact opposite of what you would do for an NA engine. In an NA engine the quench/squish area is overwhelmingly important. In a supercharged or nitrous engine its important to get rid of all the squish quench area. The pressure rise and flame travel is so fast they a high squish chamber will end gas detonate even though the squish quench is trying to cool the mixture.
If you design a port for an NA engine that's what works best in both Nitrous and supercharged engines. Some people mistakenly try and make them bigger and the engine never responds properly when you do this. I have done some pretty extensive R&D with supercharged stuff in the last 8 years and have tried many different port designs. I of course tried to get fancy and calculate how much bigger the port "should" be and every single time I enlarged it, the engine lost power". end quote
09-18-2018, 07:45 AM
#96
Kent, they had to spin the blower faster to get the boost back to where it was with the more restrictive heads. To me it shows all the more how the heads helped out. You have to compare both setups at the same boost level, or it’s not a true apples to apples comparison.
09-18-2018, 08:00 AM
#97
I respectfully disagree. With the smaller pulley, the blower is spinning faster and delivering more air into the engine. That alone would have gained power with or without the new heads. After this test, you still don’t know how much the heads helped because you don’t know how much the pulley swap helped.
I am curious about what SoFlo said in there. Why did it make more torque than HP when its well known the higher you rev the blower setup the more HP you make, not torque. I did love....
Im sure a good bit more power was made at lower boost with the same pulley but the blower speed needed to be increased to make the same boost value (aka "measure of back pressure") with the deeper breathing MMS 235 NFI heads but boosted engines should always be compared at the same boost levels to keep things on an even playing field.