Huge error in thinking by most people on this site (shorty headers)
09-12-2008, 04:57 PM
#21
Thanks for the information posted here guys... I was curious abou this because my LT1 car was a COMPLETELY different car with BBK Shorties over the stock manifolds...my LS1 car seems to have 'fake shorties' already on it... at least the factory stuff closely resembles my old headers.
Hmm..time to do some more searches....
Hmm..time to do some more searches....
09-12-2008, 08:20 PM
#22
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No. Only '98-'99 get the rolled stainless manifolds, the '00-'02 cars all get the cast iron "shorty-style" manifolds. I know this 100% for sure, since I've owned one of every year (except '01). The difference between the two is likely 2-3hp on an otherwise stock car. Might be a noticeable difference if the car already had heads/cam and ORY.
Just a change in weather can make a car "feel" faster. Sometimes my cars will feel quite a bit faster going from 80* daytime highs to 60* lows at night, with zero changes to the engine. Unless you have track times or dyno numbers, then I don't see this as any kind of "myth-busting" post.
Shorties are good for emissions compliance, and to prevent clearance issues/banging. I'd rather do mids though, you won't have clearance issues there either, and the power gains will be better. I'd only do shorties if I was really concerned about emissions.
Just a change in weather can make a car "feel" faster. Sometimes my cars will feel quite a bit faster going from 80* daytime highs to 60* lows at night, with zero changes to the engine. Unless you have track times or dyno numbers, then I don't see this as any kind of "myth-busting" post.
Shorties are good for emissions compliance, and to prevent clearance issues/banging. I'd rather do mids though, you won't have clearance issues there either, and the power gains will be better. I'd only do shorties if I was really concerned about emissions.
09-12-2008, 08:36 PM
#23
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are you trying to say that because gutting cats only nets 1-2 hp and that shorties only net 1-2, and because your gutted your cats resulted in a significant increase on your butt dyno that the shorties must also net more?
still seems like everything is speculation in here.
also, the JBA site lists the hp increase as 12, not 15.
still seems like everything is speculation in here.
also, the JBA site lists the hp increase as 12, not 15.
09-12-2008, 08:40 PM
#24
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The thing about shorties is that you have to look at what you had prior to shorty headers.
In the case of a 98-2000 car, you will find some decent gains over stock. Why? It's because of the fact that those headers are LOG STYLE HEADERS.
If you have a 01-02, the gains will be minimal. this is where the whole 1-2HP myth comes. 01-02 exhaust manifolds ARE shorty designs. Not the best design as it's cast, but the general shape and flow resemble shorties.
Now why would someone tout longtubes? Well I DO have dyno sheets comparing the 2. I have one dyno sheet showing 325ft/lb of torque and 306HP, then I have ONLY the exhaust done, Longtubes + true duals with cats and full size mufflers out the back.
That dyno run on the same dyno showed 359ft/lb of torque and 349HP. So while you may have gained 15HP, you could have potentially gained 40HP with longtubes. The price was about $800 for my longtubes so unless emissions are vital to you, I'd keep off the shorties are for everyone bandwagon and take into account which year car and what area someone lives in before indicating we are making huge errors about shorties. It's simply a generalization of something that does have some substantial truth to it, but to keep people from making decisions they regret it's sometimes necessary to push in the longtube direction. It's all because in the end, we've been there and realize that no matter what you do, its NEVER ENOUGH. You will always want more power and you will always want to spend the least amount possible to make that happen.
Finally you state you gutted the cats making the whole keep emissions legal a pointless reason for going shorties in the first place?!? Mind you I've got longtubes and I've tuned it to pass emissions, AIR is still on AND I still use EGR... so I'd only fail a visual, which thankfully I don't have to worry about.
In the case of a 98-2000 car, you will find some decent gains over stock. Why? It's because of the fact that those headers are LOG STYLE HEADERS.
If you have a 01-02, the gains will be minimal. this is where the whole 1-2HP myth comes. 01-02 exhaust manifolds ARE shorty designs. Not the best design as it's cast, but the general shape and flow resemble shorties.
Now why would someone tout longtubes? Well I DO have dyno sheets comparing the 2. I have one dyno sheet showing 325ft/lb of torque and 306HP, then I have ONLY the exhaust done, Longtubes + true duals with cats and full size mufflers out the back.
That dyno run on the same dyno showed 359ft/lb of torque and 349HP. So while you may have gained 15HP, you could have potentially gained 40HP with longtubes. The price was about $800 for my longtubes so unless emissions are vital to you, I'd keep off the shorties are for everyone bandwagon and take into account which year car and what area someone lives in before indicating we are making huge errors about shorties. It's simply a generalization of something that does have some substantial truth to it, but to keep people from making decisions they regret it's sometimes necessary to push in the longtube direction. It's all because in the end, we've been there and realize that no matter what you do, its NEVER ENOUGH. You will always want more power and you will always want to spend the least amount possible to make that happen.
Finally you state you gutted the cats making the whole keep emissions legal a pointless reason for going shorties in the first place?!? Mind you I've got longtubes and I've tuned it to pass emissions, AIR is still on AND I still use EGR... so I'd only fail a visual, which thankfully I don't have to worry about.
09-14-2008, 12:59 AM
#25
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are you trying to say that because gutting cats only nets 1-2 hp and that shorties only net 1-2, and because your gutted your cats resulted in a significant increase on your butt dyno that the shorties must also net more?
still seems like everything is speculation in here.
also, the JBA site lists the hp increase as 12, not 15.
still seems like everything is speculation in here.
also, the JBA site lists the hp increase as 12, not 15.
I was simply sharing my experience vs. what the dyno sheet proved. I also mentioned that I "felt" the difference, and it wasn't just because of a weather change, it was all the time. I'm not advocating shorty's or long tubes or saying shorty's are great or bad, vs. longtubes or any kind of comparison. All I did was say, here is what I did, here are the results, and there is a dyno sheet for proof. Take it or leave it!
P.S. the collectors on mine are the exact same as long tubes!
Thanks for reading!
09-14-2008, 01:28 AM
#26
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The thing about shorties is that you have to look at what you had prior to shorty headers.
In the case of a 98-2000 car, you will find some decent gains over stock. Why? It's because of the fact that those headers are LOG STYLE HEADERS.
If you have a 01-02, the gains will be minimal. this is where the whole 1-2HP myth comes. 01-02 exhaust manifolds ARE shorty designs. Not the best design as it's cast, but the general shape and flow resemble shorties.
Now why would someone tout longtubes? Well I DO have dyno sheets comparing the 2. I have one dyno sheet showing 325ft/lb of torque and 306HP, then I have ONLY the exhaust done, Longtubes + true duals with cats and full size mufflers out the back.
That dyno run on the same dyno showed 359ft/lb of torque and 349HP. So while you may have gained 15HP, you could have potentially gained 40HP with longtubes. The price was about $800 for my longtubes so unless emissions are vital to you, I'd keep off the shorties are for everyone bandwagon and take into account which year car and what area someone lives in before indicating we are making huge errors about shorties. It's simply a generalization of something that does have some substantial truth to it, but to keep people from making decisions they regret it's sometimes necessary to push in the longtube direction. It's all because in the end, we've been there and realize that no matter what you do, its NEVER ENOUGH. You will always want more power and you will always want to spend the least amount possible to make that happen.
Finally you state you gutted the cats making the whole keep emissions legal a pointless reason for going shorties in the first place?!? Mind you I've got longtubes and I've tuned it to pass emissions, AIR is still on AND I still use EGR... so I'd only fail a visual, which thankfully I don't have to worry about.
In the case of a 98-2000 car, you will find some decent gains over stock. Why? It's because of the fact that those headers are LOG STYLE HEADERS.
If you have a 01-02, the gains will be minimal. this is where the whole 1-2HP myth comes. 01-02 exhaust manifolds ARE shorty designs. Not the best design as it's cast, but the general shape and flow resemble shorties.
Now why would someone tout longtubes? Well I DO have dyno sheets comparing the 2. I have one dyno sheet showing 325ft/lb of torque and 306HP, then I have ONLY the exhaust done, Longtubes + true duals with cats and full size mufflers out the back.
That dyno run on the same dyno showed 359ft/lb of torque and 349HP. So while you may have gained 15HP, you could have potentially gained 40HP with longtubes. The price was about $800 for my longtubes so unless emissions are vital to you, I'd keep off the shorties are for everyone bandwagon and take into account which year car and what area someone lives in before indicating we are making huge errors about shorties. It's simply a generalization of something that does have some substantial truth to it, but to keep people from making decisions they regret it's sometimes necessary to push in the longtube direction. It's all because in the end, we've been there and realize that no matter what you do, its NEVER ENOUGH. You will always want more power and you will always want to spend the least amount possible to make that happen.
Finally you state you gutted the cats making the whole keep emissions legal a pointless reason for going shorties in the first place?!? Mind you I've got longtubes and I've tuned it to pass emissions, AIR is still on AND I still use EGR... so I'd only fail a visual, which thankfully I don't have to worry about.
i agree, if i would have listened to a whole lot of people at the time i would have never bought my mac mids. i like them and all, no clearence issues,made decent power 336rwhp. but with my pending H/C coming soon i will need to upgrade to LT'sto make the best power and flow the best.
if i would have none then what i do now, LT's all the way
09-14-2008, 01:34 AM
#27
There are a lot of inexperienced "tuners" on ls1tech. That's not to say they don't know anything, just not the whole picture.
Exhaust primary tuning has a lot of a variables and most people just go with what everyone else is doing because they don't understand how the primary length and diameter affect power and torque curves.
I could probably write 3-4 pages of posts on how this all works, but only about 2% of members would actually understand it. And they typically already know this info.
That is what the Advanced Engineering section is for.
As for the general populous, the old "copy what works" building is plenty fine for what they need.
As for myself....I like longtubes because I like a good balance between high rpm power and low rpm torque, because I like to cruise the car and go to the strip.
Exhaust primary tuning has a lot of a variables and most people just go with what everyone else is doing because they don't understand how the primary length and diameter affect power and torque curves.
I could probably write 3-4 pages of posts on how this all works, but only about 2% of members would actually understand it. And they typically already know this info.
That is what the Advanced Engineering section is for.
As for the general populous, the old "copy what works" building is plenty fine for what they need.
As for myself....I like longtubes because I like a good balance between high rpm power and low rpm torque, because I like to cruise the car and go to the strip.
09-14-2008, 07:35 AM
#28
What was funny about longtubes is that I had the opposite experience on the "butt-dyno". I thought my car felt slower the first time I drove it after 13 hours straight of doing headers.
What I hadn't realized is how much the torque curve had changed over stock.
At stock, the torque curve was flat. The difference in torque from 1500 rpm to 2500 rpm was probably <30 ft/lb and from 2500-6000 it was between 310-325 at peak. Pretty flat by most standards.
With the headers in, the "limit" of the cam was pretty much reached, sub 2k felt the same, 2500 woke up a bit and 4k was a freak. Literally when 4k came along 3900 was about 340ft/lb and then 4k shot to 359 and held it from 4k to 5k rpm. the average from 2500-4000 was about 335ft/lb.
With that difference in hp, I thought oh I lost down low torque and maybe gained a bit on the upper rpm. Though the behavior of the car was to pretty much break loose the tires from 2k onward on "small clutch dumps".
I think in all honesty it is our nature to feel the cheapest mods do more and the more expensive and hardworking mods to do less. I swore when I did a lid the butt dyno alarm went off like hey I can feel it do more. Gain was nowhere near what headers did.
Heck when I run my stock 245 16 rims, I thought my clutch was slipping. Turns out 245 can't hold the torque my engine's putting out and going half throttle to WOT is instant tire spin at lower speeds ie under 30mph. Fell is VERY subjective I think.
As for my exhaust, QTP Longtubes, though my opinion is that ARH, Kooks and QTP will probably net you the same amount so just go with price (as long as QTP have their quality control fixed). I bought mine just before that whole issue a year and a half ago. True duals are custom fabbed. Cost was cheap though, luck will vary in areas finding a shop that can do things reasonably.
What I hadn't realized is how much the torque curve had changed over stock.
At stock, the torque curve was flat. The difference in torque from 1500 rpm to 2500 rpm was probably <30 ft/lb and from 2500-6000 it was between 310-325 at peak. Pretty flat by most standards.
With the headers in, the "limit" of the cam was pretty much reached, sub 2k felt the same, 2500 woke up a bit and 4k was a freak. Literally when 4k came along 3900 was about 340ft/lb and then 4k shot to 359 and held it from 4k to 5k rpm. the average from 2500-4000 was about 335ft/lb.
With that difference in hp, I thought oh I lost down low torque and maybe gained a bit on the upper rpm. Though the behavior of the car was to pretty much break loose the tires from 2k onward on "small clutch dumps".
I think in all honesty it is our nature to feel the cheapest mods do more and the more expensive and hardworking mods to do less. I swore when I did a lid the butt dyno alarm went off like hey I can feel it do more. Gain was nowhere near what headers did.
Heck when I run my stock 245 16 rims, I thought my clutch was slipping. Turns out 245 can't hold the torque my engine's putting out and going half throttle to WOT is instant tire spin at lower speeds ie under 30mph. Fell is VERY subjective I think.
As for my exhaust, QTP Longtubes, though my opinion is that ARH, Kooks and QTP will probably net you the same amount so just go with price (as long as QTP have their quality control fixed). I bought mine just before that whole issue a year and a half ago. True duals are custom fabbed. Cost was cheap though, luck will vary in areas finding a shop that can do things reasonably.
09-14-2008, 12:24 PM
#29
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My car, an 02 Z28 with mild H/C, went from 393/365 with edelbrock shorties and stock cats, to numbers in sig with Pacesetters and highflow cats being the only change.
09-14-2008, 06:24 PM
#31
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Exactly.
You cannot use the vendor's website dyno sheet as proof. They can fabricate any 'proof' they want. 90% of statistics can be made to say anything you want, 50% of the time. If you did a before and after dyno on your car, or before and after track runs, then you'd have actual proof. All you have in this thread is speculation based on what you feel.
Now, I'm not saying you didn't gain anything. But there is no way you can put a number on what you "feel" before and after, nor can you say that the gains were significant without some solid numbers.
09-14-2008, 06:30 PM
#32
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Unless you're looking to set/break records, explore new ground, or introduce a product to market that will exceede your competition, there is no need to re-invent the wheel.
There are TONS of documented LSx build-ups, just on this very site. For the average hot rodder just looking to build a quick street/strip cruiser, reading & coping is the easiest way to achieve the desired results. That's what makes sites like this so useful, the exchange of information reduces the need for trial and error.
09-15-2008, 06:08 AM
#33
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i have a set of jba shorties, i couldnt afford long tubes, but i got the stainless jbas for 150 dollars. it saved me from buying a y pipe right away. wich i have a slp on its way friday. going through lm2 exhaust. i know they helped but how much no clue. but i was able to piece together full stainless exhaust for the price of lts. plus no clearence issues at all with them. they are a nicely built header just like the pacesetter lts that i helped my freind install. its all about your budget.
09-15-2008, 06:27 AM
#34
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Well I would take this thread and that dyno graph with a grain of salt. The stock pass was only 273 rwhp. That's kind of low for a LS1 so I'm not personally convinced those gains are accurate.
Take a strong dynoing 00-02 model LS1 and I bet the gains are a wee bit less.
https://ls1tech.com/forums/generation-iii-external-engine/520845-mod-guide-induction-exhaust-please-read-before-posting.html
They don't put myths in the stickies here at ls1tech. Shorties only have one use as far as I'm concerned. Anyone with a 98-99 LS1 that has to remain 100% emission legal (california residents for example). For everyone else, I wouldn't waste the time or money on shorties.
LT's or bust!
Take a strong dynoing 00-02 model LS1 and I bet the gains are a wee bit less.
https://ls1tech.com/forums/generation-iii-external-engine/520845-mod-guide-induction-exhaust-please-read-before-posting.html
They don't put myths in the stickies here at ls1tech. Shorties only have one use as far as I'm concerned. Anyone with a 98-99 LS1 that has to remain 100% emission legal (california residents for example). For everyone else, I wouldn't waste the time or money on shorties.
LT's or bust!
09-15-2008, 07:31 AM
#35
I felt a SOTP difference when i went from humid weather to average weather when my cats were removed. Doesnt mean that i gained 15hp. You could have had a 20 difference in temp when you did this. I have a real hard time believing that by me spending $900 on these miracle headers will give me 15hp with the cats still on and a even "faster" car with them off. A good tune will give you a SOTP difference with a stock car.
09-15-2008, 09:48 AM
#37
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I wish I had the time and money to do a before and after, I'd be the one laughing 
If I wanted to do anything with this thread, which I havn't said already, it was to disprove the 1-2 hp myth.
I think it's kinda shady nobody here believes dyno graphs however. Anytime I see a dyno graph, be like, nope didn't happen. "You just saw my car do the dyno pull then I showed you the dyno graph on the screen". Your lying, that was another car; you just pulled up another cars dyno graph on the computer.. "I also have time slips" those could be faked with a 1970 calculator and the video edited with a mac...
If I wanted to do anything with this thread, which I havn't said already, it was to disprove the 1-2 hp myth. I think it's kinda shady nobody here believes dyno graphs however. Anytime I see a dyno graph, be like, nope didn't happen. "You just saw my car do the dyno pull then I showed you the dyno graph on the screen". Your lying, that was another car; you just pulled up another cars dyno graph on the computer.. "I also have time slips" those could be faked with a 1970 calculator and the video edited with a mac...
09-15-2008, 10:04 AM
#38
Manufacturers post dyno graphs all the time. The problem is that DATA can be outright forged or just exaggerated to make the product appear more appealing. QTP claimed up to 40hp gain, but I'd still take that with a grain of salt. Why? I had the LS6 Intake, a lid, the LS7 clutch and LS2 Flywheel (which is a loss of power) for that 306HP. Then there's the fact I added 2.5 inch true duals. The reality is that perhaps bone stock, I might have only gained 25HP but with the support of the other items in combination, I gained more. It could be that the headers alone would add 30HP to a stock 98 and with supporting mods gain more. Butt dyno means squat, and manufacturers numbers mean even less as you will NOT have the exact same combination that was used.
When I say I went from 306HP to 349HP, I literally meant I took my car on a dyno BEFORE the headers, got a base run, THEN I put on the headers and took the car on the SAME dyno and got some new dyno numbers.
While I will keep in mind that there is a standard deviation that can apply due to weather, engine condition (time between the dyno sessions was 6 months), fuel etc, the gain is significant and real. I will post dyno sheets later what I and others consider REAL WORLD proven results from downright bleeding knuckles 13 hour install of parts can do for anyone's 98 car that is in reasonably good condition.
If you take into account the DIFFERENCE in years, you will also find that a 01 or 02 may NOT gain as much HP as I gained over their base dyno for that car. There is a cam difference, a TB difference and a stock manifold difference.
You didn't disprove anything, you simply stated that you felt a difference AND you showed us manufacturers gains on their car, not yours. I'm not saying you didn't gain, but what you think you gained versus what the manufacturer says you gained are much different results.
If I go by rated gains, then here's my base
298HP
Lid +10
LS6 Intake +10-15
QTP Headers +40
True duals +10
Hi-flow cats versus stock +5
TR224 Cam +20
Underdrive pulley +10-15
Ported TB +10
Should be at 423HP at the wheels now... oh wait... 380RWHP... hmmm that's odd... but wait, manufacturers don't lie! So my but must be right, I'm running 423HP!
When I say I went from 306HP to 349HP, I literally meant I took my car on a dyno BEFORE the headers, got a base run, THEN I put on the headers and took the car on the SAME dyno and got some new dyno numbers.
While I will keep in mind that there is a standard deviation that can apply due to weather, engine condition (time between the dyno sessions was 6 months), fuel etc, the gain is significant and real. I will post dyno sheets later what I and others consider REAL WORLD proven results from downright bleeding knuckles 13 hour install of parts can do for anyone's 98 car that is in reasonably good condition.
If you take into account the DIFFERENCE in years, you will also find that a 01 or 02 may NOT gain as much HP as I gained over their base dyno for that car. There is a cam difference, a TB difference and a stock manifold difference.
You didn't disprove anything, you simply stated that you felt a difference AND you showed us manufacturers gains on their car, not yours. I'm not saying you didn't gain, but what you think you gained versus what the manufacturer says you gained are much different results.
If I go by rated gains, then here's my base
298HP
Lid +10
LS6 Intake +10-15
QTP Headers +40
True duals +10
Hi-flow cats versus stock +5
TR224 Cam +20
Underdrive pulley +10-15
Ported TB +10
Should be at 423HP at the wheels now... oh wait... 380RWHP... hmmm that's odd... but wait, manufacturers don't lie! So my but must be right, I'm running 423HP!
Last edited by SladeX; 09-15-2008 at 10:11 AM.
09-15-2008, 11:41 AM
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Manufacturers post dyno graphs all the time. The problem is that DATA can be outright forged or just exaggerated to make the product appear more appealing. QTP claimed up to 40hp gain, but I'd still take that with a grain of salt. Why? I had the LS6 Intake, a lid, the LS7 clutch and LS2 Flywheel (which is a loss of power) for that 306HP. Then there's the fact I added 2.5 inch true duals. The reality is that perhaps bone stock, I might have only gained 25HP but with the support of the other items in combination, I gained more. It could be that the headers alone would add 30HP to a stock 98 and with supporting mods gain more. Butt dyno means squat, and manufacturers numbers mean even less as you will NOT have the exact same combination that was used.
When I say I went from 306HP to 349HP, I literally meant I took my car on a dyno BEFORE the headers, got a base run, THEN I put on the headers and took the car on the SAME dyno and got some new dyno numbers.
While I will keep in mind that there is a standard deviation that can apply due to weather, engine condition (time between the dyno sessions was 6 months), fuel etc, the gain is significant and real. I will post dyno sheets later what I and others consider REAL WORLD proven results from downright bleeding knuckles 13 hour install of parts can do for anyone's 98 car that is in reasonably good condition.
If you take into account the DIFFERENCE in years, you will also find that a 01 or 02 may NOT gain as much HP as I gained over their base dyno for that car. There is a cam difference, a TB difference and a stock manifold difference.
You didn't disprove anything, you simply stated that you felt a difference AND you showed us manufacturers gains on their car, not yours. I'm not saying you didn't gain, but what you think you gained versus what the manufacturer says you gained are much different results.
If I go by rated gains, then here's my base
298HP
Lid +10
LS6 Intake +10-15
QTP Headers +40
True duals +10
Hi-flow cats versus stock +5
TR224 Cam +20
Underdrive pulley +10-15
Ported TB +10
Should be at 423HP at the wheels now... oh wait... 380RWHP... hmmm that's odd... but wait, manufacturers don't lie! So my but must be right, I'm running 423HP!
When I say I went from 306HP to 349HP, I literally meant I took my car on a dyno BEFORE the headers, got a base run, THEN I put on the headers and took the car on the SAME dyno and got some new dyno numbers.
While I will keep in mind that there is a standard deviation that can apply due to weather, engine condition (time between the dyno sessions was 6 months), fuel etc, the gain is significant and real. I will post dyno sheets later what I and others consider REAL WORLD proven results from downright bleeding knuckles 13 hour install of parts can do for anyone's 98 car that is in reasonably good condition.
If you take into account the DIFFERENCE in years, you will also find that a 01 or 02 may NOT gain as much HP as I gained over their base dyno for that car. There is a cam difference, a TB difference and a stock manifold difference.
You didn't disprove anything, you simply stated that you felt a difference AND you showed us manufacturers gains on their car, not yours. I'm not saying you didn't gain, but what you think you gained versus what the manufacturer says you gained are much different results.
If I go by rated gains, then here's my base
298HP
Lid +10
LS6 Intake +10-15
QTP Headers +40
True duals +10
Hi-flow cats versus stock +5
TR224 Cam +20
Underdrive pulley +10-15
Ported TB +10
Should be at 423HP at the wheels now... oh wait... 380RWHP... hmmm that's odd... but wait, manufacturers don't lie! So my but must be right, I'm running 423HP!
Of course numbers are inflated, I know their very subjective and one result will not fit every car, and sure they can be exaggerated. Even if you take half of there stated value, that still better than 1-2 hp, by 3x-6x. I remember everybody saying shorties where 1-2 hp and that's it. I know for a fact I can feel my car pull harder at the top end, it's not in my head or due to weather changes, i've done it about 10 times on various days. If anything, just take away that they are not worthless, there is hp gains, and that the reasons for going this route were already stated.
I think all the information is out there, unless anybody has something new to add. I think this was informative, and this is what the site needs. Well besides a few of these lasts posts anyways. Probably done posting in this one, thanks for challenging me.
Ryan