Headers alone gains???
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Melting Slicks
Joined: Jan 2004
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From: walkersville md
Headers alone gains???
I wannak now what yall got as far as Hp/TRQ increase, with what brand headers. No tune, no anythign else, if possible, just headers. before and after..... Lookin to see what headers get the most gain total. I looked and looked and found little to no info on ppl's gains with JUST headers, every1 else had other mods.... TY - Roger
Team Owner
Joined: Sep 1999
Posts: 20,054
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From: Swansea IL
I gained 25 RWHP/Torque on my 99 LS1 w/o a tune. With a tune I may have gained another 8 to 10. I was runing real rich and installing the LT leaned the car just enough that I didn't really need or want a tune.
Loads of variables, but ball park HP gains of 25 are common.
Tom
Loads of variables, but ball park HP gains of 25 are common.
Tom
Burning Brakes
Joined: Aug 2000
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I just talked to a tuner and said I was wasting my money by tuning with only the addition of headers, intake and exhaust. He could have made an easy $200 off of me, but instead said it wasn't worth it, he claimed that the factory computer will adjust to air/exhaust flow changes with time (takes some miles). He only said it would be necessary to tune if I installed cam or heads or supercharger, etc.
Tech Contributor
Joined: Mar 2003
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Originally Posted by NASTYZO6
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Tech Contributor
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Originally Posted by Zred06
I just talked to a tuner and said I was wasting my money by tuning with only the addition of headers, intake and exhaust. He could have made an easy $200 off of me, but instead said it wasn't worth it, he claimed that the factory computer will adjust to air/exhaust flow changes with time (takes some miles). He only said it would be necessary to tune if I installed cam or heads or supercharger, etc.
Burning Brakes
Joined: Nov 2004
Posts: 1,031
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From: Crete IL
Originally Posted by Zred06
I just talked to a tuner and said I was wasting my money by tuning with only the addition of headers, intake and exhaust. He could have made an easy $200 off of me, but instead said it wasn't worth it, he claimed that the factory computer will adjust to air/exhaust flow changes with time (takes some miles). He only said it would be necessary to tune if I installed cam or heads or supercharger, etc.
Burning Brakes
Joined: Aug 2000
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Originally Posted by SpinMonster
Not true. While the PCM can compensate for long term fuel trends within a range, the change that headers cause is a lean condition in closed loop which causes the PCM to compensate at wide open throttle by dumping fuel that causes the car to be super rich there. This is bad. If your tuner doesnt know this then I wouldnt let him tune my car even if I could get it for 200 bucks.
Melting Slicks
Joined: Nov 2003
Posts: 2,312
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From: Ridgeland MS
St. Jude Donor '06-'07-'08-'09-'10-'11
Originally Posted by Zred06
I sure would like to see evidence of this, then I could go to the tuner and show them. I hear a lot of opinions on this forum and I would like to see the facts.
You mean that we should't believe everything written here? My my. LOL Bill
Burning Brakes
Joined: Aug 2000
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A little further follow-up, I talked to a second tuner today who told me it was $500 for custom tuning but he talked me out of doing it sice he said it won't give more than 5-10 hp increase. He said if you just add headers alone, there would be benefit in tuning but when you add a Cold Air intake then the balance between exhaust and intake is restored to within the range of compensation that the factory PCM can adjust to (+/- 15% FAR variance). So I am fairly well convinced that I really willl not get much bang for my buck from tuning....unless someone can prove it to me with facts.
Melting Slicks
Joined: Aug 2005
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Originally Posted by Zred06
A little further follow-up, I talked to a second tuner today who told me it was $500 for custom tuning but he talked me out of doing it sice he said it won't give more than 5-10 hp increase. He said if you just add headers alone, there would be benefit in tuning but when you add a Cold Air intake then the balance between exhaust and intake is restored to within the range of compensation that the factory PCM can adjust to (+/- 15% FAR variance). So I am fairly well convinced that I really willl not get much bang for my buck from tuning....unless someone can prove it to me with facts.
Race Director
Joined: Mar 2005
Posts: 11,549
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From: Southampton NJ
Originally Posted by Kappa
I think tuning has a big effect on these cars. My friend installed a Vararam on his '03 Z06 and after driving it around for a few weeks had it on the dyno. The car made 355rwhp and the guys at MTI Racing found that the computer could not compensate for the extra air as the injectors were at a 100% duty cycle! 2 days later under similar conditions and tuning the car made 377rwhp.
that wasn't an ls2
Burning Brakes
Joined: Aug 2000
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Originally Posted by Kappa
I think tuning has a big effect on these cars. My friend installed a Vararam on his '03 Z06 and after driving it around for a few weeks had it on the dyno. The car made 355rwhp and the guys at MTI Racing found that the computer could not compensate for the extra air as the injectors were at a 100% duty cycle! 2 days later under similar conditions and tuning the car made 377rwhp.
Le Mans Master
Joined: Sep 2004
Posts: 7,027
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From: Shiloh Ohio
I would not spend that sort of money on these mods and not get the car dyno tuned. I agree with the spin monster on this one.
You say you want some proof, well I have none. But I have been reading posts on C5's and C6's for a couple years now and I can tell you a tune helps.
On my two C5's I just used a handheld tuner and it made a significant difference in performance. Around 2 tenths in the qtr mile, so I know a dyno tune would be at least this if not another tenth.
I think you will see close to a 15-20 HP difference between a tune and no tune with a CAI and Long tube header install.
Just my opinion.
You say you want some proof, well I have none. But I have been reading posts on C5's and C6's for a couple years now and I can tell you a tune helps.
On my two C5's I just used a handheld tuner and it made a significant difference in performance. Around 2 tenths in the qtr mile, so I know a dyno tune would be at least this if not another tenth.
I think you will see close to a 15-20 HP difference between a tune and no tune with a CAI and Long tube header install.
Just my opinion.
Drifting
Joined: Jul 2005
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From: az
a tune will help to get rid of timing retard on hard shifts, lean out the a/f ratio a little (within reason) and add a few degreees of timing here and there, these three changes will add 8-15ish hp/tq or more (depending on how aggressive the tune is). as far as the headers and air intake are concern, the pcm while in close loop will be able to see the increase in air flow (caused by the better intake and exhaust) from mass air meter data and add additional fuel to stay within the predetermine wot a/f ratio. (there will be some fine long and short term fuel adjustments) i am assuming the injectors are still under 100% duty cycle, i am sure it is if that is all your mods. so you will see gain from your mods without a tune....just no additional hp/tq from lean out wot a/f ratio / getting rid of timing retard on hard shifts or additional timing. 
Last edited by cbrf4i1; Mar 26, 2006 at 05:36 AM.