LT Headers: The Truth Behind the Claims?
Burning Brakes
Joined: Feb 2004
Posts: 831
Likes: 0
From: Country Boys Can Survive.
Originally Posted by EB20003
I'm not touching that one Something definitely does not sound right about that. I am at 323.8hp/339.6tq with the stock heads, the mods in my signature, and no tune after the KOOKS headers. Thats only 9rwhp/ 5rwtq lower than your car with Patriot 5.3 heads.
And I'm running 3.42s and a 2600 stall to your 3.15s and stock converter.
Team Owner
Joined: Aug 2003
Posts: 38,314
Likes: 35
Originally Posted by loudsam
At the risk of jacking the thread; How do you like the 3.42's with your t/c? I'm running the 2800 stall through 3.15's and I like it!!! BTW; I was, (more or less), just generalizing with the line you quoted, (that you wouldn't touch). I guess I just meant that you can "jerk around" dyno results quite a bit.
BTW, I love my 3.42s and 2600 stall.
Drifting
Joined: Jul 2004
Posts: 1,663
Likes: 16
From: DFW Texas
Some people around here also get upset when people's cars make more power with bolt-ons then others. If your car happens to make good power then something has to be screwy. 
Last edited by CNB; Mar 25, 2005 at 11:50 PM.
Le Mans Master
Joined: Mar 2004
Posts: 5,562
Likes: 5
From: South East coast Florida
Originally Posted by Icemanskis
Hello all,
Last weekend a set of dynatech supermaxx headers were installed on my 2000 coupe. Prior mods include magnaflow catback exhaust with an x-pipe and a blackwing. This past december I had my vette tuned with only the exhaust and intake. My baseline dyno was around 288 rwhp and 307rwtq. Following the tune I dynoed at 317rwhp and 317rwtq. I was very pleased at the time with these gains (almost thirty horses with only my basic mods)!! The dyno sheet of that day is posted below.
Just today I returned to the same tuner shop after the installation of my dynatech headers (East Side Performance in Wallingford, CT). And I was incredibly dissapointed at the results. I baselined at 317rwhp and about 324rwtq. So basically, off the bat I didnt gain anything with the headers. The AFR was running quite rich at 11.6. That was leaned out and on the seventh and final pass I dynoed at 325rwhp and 334rwtq with an AFR of 12.8. The dyno sheet is posted below for today.
I was shocked that I only gained 9rwhp and 17rwtq considering I was expecting at least something close to the manufacturer's claims of 34-40hp. Basically, the shop told me that it is very common for people to come to them with headers and gain minimal power or actually lose power despite manufacturer's claims. He mentioned that the stock exhaust system is very good and the gains to be seen by these bolts on is minimal at best. However, if you crack into the engine and install an aftermarket cam or heads, this is the scenario when these bolt ons will become crucial. So it seems at though the gains I saw from the first tune were the result of editing out things like torque management and changing the timing. Hence, from my experiences, I feel as though the manufacturer's claims of such incredible hp are faulty and very subjective to other details relating to the tune itself rather than the headers. My basic impression is that bolts on are not all the valuable in and of themselves, but only valuable in combination with real engine mods such as heads, cam, forced induction. Forum member "connecticut" also witnessed the tune and spoke with the tuner. He installed my headers and knows much more about cars than myself, so I am sure he can add his comments past mine.
Brian
Last weekend a set of dynatech supermaxx headers were installed on my 2000 coupe. Prior mods include magnaflow catback exhaust with an x-pipe and a blackwing. This past december I had my vette tuned with only the exhaust and intake. My baseline dyno was around 288 rwhp and 307rwtq. Following the tune I dynoed at 317rwhp and 317rwtq. I was very pleased at the time with these gains (almost thirty horses with only my basic mods)!! The dyno sheet of that day is posted below.
Just today I returned to the same tuner shop after the installation of my dynatech headers (East Side Performance in Wallingford, CT). And I was incredibly dissapointed at the results. I baselined at 317rwhp and about 324rwtq. So basically, off the bat I didnt gain anything with the headers. The AFR was running quite rich at 11.6. That was leaned out and on the seventh and final pass I dynoed at 325rwhp and 334rwtq with an AFR of 12.8. The dyno sheet is posted below for today.
I was shocked that I only gained 9rwhp and 17rwtq considering I was expecting at least something close to the manufacturer's claims of 34-40hp. Basically, the shop told me that it is very common for people to come to them with headers and gain minimal power or actually lose power despite manufacturer's claims. He mentioned that the stock exhaust system is very good and the gains to be seen by these bolts on is minimal at best. However, if you crack into the engine and install an aftermarket cam or heads, this is the scenario when these bolt ons will become crucial. So it seems at though the gains I saw from the first tune were the result of editing out things like torque management and changing the timing. Hence, from my experiences, I feel as though the manufacturer's claims of such incredible hp are faulty and very subjective to other details relating to the tune itself rather than the headers. My basic impression is that bolts on are not all the valuable in and of themselves, but only valuable in combination with real engine mods such as heads, cam, forced induction. Forum member "connecticut" also witnessed the tune and spoke with the tuner. He installed my headers and knows much more about cars than myself, so I am sure he can add his comments past mine.
Brian
I had installed the Vararam, Dynatech's and Magnaflow Cat back which is similar to your setup except the Vararam is a true CAI. The rest of the car is stock and I have a 6 spd. I baselined at 308/327 and when was complete, left the dyno with 346/367 at 12.8/13.3 AFR. I don't know why some mod's work better for some, but not for others. I don't want to even get into the differences in Dyno's and that integrity issue
The only thing I can tell you is that the setup in my car does high 12's/109's at the track (still learning), with emt's. More importantly it pull's like a mother from idle through 5500 RPM. Have you taken the time to checkout the actual performance of your car yet? First off all the Manufacturer gains are inflated and might be based on Flywheel power and I wouldn't be surprised if they advertised similar to the "olden" days, without Alternators, water pumps etc. Additionally, you have to take off at least 18 to 20% from their claims (if based on flywheel) to compensate for loses from your A4. Plus what additional marketing inflections they may utilize.
As a note my setup was supposed to increase my Horsepower by 75. I basically got half of that! But I did get a consistant increase under the curve which translate to more power across the entire Power Curve. More importantly, I got an increase of 40 ft. lbs
Is the Blackwing and Borlas good for 30 horse at the rear wheels? How much was attributed to the tune? Why Torgue management? Seems like they got alot of horse's out of that initial mod. If you aren't happy with the subjective/seat of the pants results, then you will have to try another set of Headers to put you concerns to bed.
Good Luck and and I hope you resolve this issue and get back to perma-grin.
Last edited by mowton; Mar 26, 2005 at 09:16 AM. Reason: Added a sentence on not including Dyno differences in my post
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 232
From: SoCal
Its seems to me that from lots of sigs and posts that I have seen and read including some in this thread that your results are typical with your total mods as they currently are.
Only differnce between us is I have 3.42 gears.
326 RWHP/343 RWTQ
Only differnce between us is I have 3.42 gears.
326 RWHP/343 RWTQ
Team Owner
Joined: Aug 2003
Posts: 38,314
Likes: 35
Originally Posted by Macinamouth
Its seems to me that from lots of sigs and posts that I have seen and read including some in this thread that your results are typical with your total mods as they currently are.
Only differnce between us is I have 3.42 gears.
326 RWHP/343 RWTQ
Only differnce between us is I have 3.42 gears.
326 RWHP/343 RWTQ
Last edited by '06 Quicksilver Z06; Mar 26, 2005 at 03:33 AM.
Racer
Joined: Mar 2005
Posts: 475
Likes: 0
From: Euless TX
Why does the corvette dyno so much lower than the fbodys. With only a lid and exhaust with stock headers I dynoed 321 rwhp in my ta with an m6 and have seen people dyno 340+ with long tubes on a f-body.
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Burning Brakes
Joined: Sep 2004
Posts: 755
Likes: 0
From: Portland Oregon
man i wonder why all vettes are not craated equal. 
I have a 2000 M6 with vararam and B&B cat back and im throwing down 335-345 to the wheels. I also have supermax headers in the mail so will see what happens. 
I have a 2000 M6 with vararam and B&B cat back and im throwing down 335-345 to the wheels. I also have supermax headers in the mail so will see what happens.
Burning Brakes
Joined: Feb 2004
Posts: 831
Likes: 0
From: Country Boys Can Survive.
I just HAD to add another .02 cents worth. To begin with, I truly LOVE the fact that we say what we think, (for the most part), on this forum.
When I bought and installed my header system, (Supermaxx complete system), I REALLY didn't care how much dyno-performance they ALONE were going to add. I will NEVER race a dyno! I'm totally against it! Common sense however told me the headers would be worth a WHOLE LOT of performance down the road when I installed OTHER mods.
I have been brow-beaten about whether or not I've researched the performance upgrades that I've done. I HAVE researched the subject EXTENSIVELY! And, I was fortunate this winter, and I was able to FIND the money to have done what I wanted to have done.
When I picked up my '99 a4 c5 coupe from LPE a week or so ago, They handed me the folder they provide when they complete the job. The dyno sheet was there, as well as other stuff. LPE NEVER elaborated on the dyno #'s. I never questioned anything. I took the car to a lonely road nearby after I had warmed the engine/drivetrain. When I was done on THAT road, I could care less about DYNO #'s! And I don't have even a little trace of doubt that my headers are doing the job I INTENDED them to do!
When I bought and installed my header system, (Supermaxx complete system), I REALLY didn't care how much dyno-performance they ALONE were going to add. I will NEVER race a dyno! I'm totally against it! Common sense however told me the headers would be worth a WHOLE LOT of performance down the road when I installed OTHER mods.
I have been brow-beaten about whether or not I've researched the performance upgrades that I've done. I HAVE researched the subject EXTENSIVELY! And, I was fortunate this winter, and I was able to FIND the money to have done what I wanted to have done.
When I picked up my '99 a4 c5 coupe from LPE a week or so ago, They handed me the folder they provide when they complete the job. The dyno sheet was there, as well as other stuff. LPE NEVER elaborated on the dyno #'s. I never questioned anything. I took the car to a lonely road nearby after I had warmed the engine/drivetrain. When I was done on THAT road, I could care less about DYNO #'s! And I don't have even a little trace of doubt that my headers are doing the job I INTENDED them to do!
Last edited by loudsam; Mar 26, 2005 at 09:47 AM.
Le Mans Master
Joined: Aug 2004
Posts: 6,723
Likes: 1,089
From: NE OH
St. Jude Donor '09-'10
Originally Posted by killaz
man i wonder why all vettes are not craated equal. I have a 2000 M6 with vararam and B&B cat back and im throwing down 335-345 to the wheels. I also have supermax headers in the mail so will see what happens.
I have a 2000 M6 with vararam and B&B cat back and im throwing down 335-345 to the wheels. I also have supermax headers in the mail so will see what happens.
Burning Brakes
Joined: Feb 2004
Posts: 831
Likes: 0
From: Country Boys Can Survive.
Originally Posted by BudgetPlan1
I think i wanna put my car on this dyno
Burning Brakes
Joined: Feb 2004
Posts: 831
Likes: 0
From: Country Boys Can Survive.
Originally Posted by EB20003
Well again a word of "caution" Loudsam. Some people here get real upset when you imply that dyno results can be manipulated. Just a word to the wise.
BTW, I love my 3.42s and 2600 stall.
BTW, I love my 3.42s and 2600 stall.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
When I posted my QTP dyno results, I took a lot of crap because the pundits didn't think the gain was enough. I even had a forum vendor send me a private e-mail on the matter. But my numbers I felt were an honest gain. Didn't tweak the AFR or other things to make them look like there was more power there. As a matter of fact, I had higher dyno runs but we discussed the matter and put in a very conservative tune. I am at 12:1 at 5500 RPM and up. There are some 04's that have put down very good gains with no tune at all. Overall, I think you may be a bit low with those headers on peak, but you should cross plot your before and after to see how you did mid-range. I think that would add a lot to this discussion.
Pro
Joined: Nov 2003
Posts: 532
Likes: 0
From: herminston oregon
headers
Originally Posted by EB20003
Thats too bad. You are the second person, CNB was the other, I have seen end up with disappointing results following the Dynatechs.
Some are attributing this to the 2 1/2 in x pipe in the dynatech system.
This may be what happened in your case. It would have been interesting to see, what your results would have been had you been running a system with a 3 inch X pipe like KOOKS or LGs.
I think the shop may be trying to sell you a heads and cam install. I have never heard of editing out torque management increasing anyone's peak horsepower. TM is there to prevent the breakage of driveline parts on sudden acceleration.
I have KOOKS and I haven't had torque management since long before their install. I was previously running the Predator performance tune.
I picked up 25 RWHP/ 30 RWTQ with my KOOKS and 3 in x pipe and high flow cats. WIth no tuning.
Then I had the car tuned with the KOOKS and picked up another 2-3 tenths in the quarter mile.
Some are attributing this to the 2 1/2 in x pipe in the dynatech system.
This may be what happened in your case. It would have been interesting to see, what your results would have been had you been running a system with a 3 inch X pipe like KOOKS or LGs.
I think the shop may be trying to sell you a heads and cam install. I have never heard of editing out torque management increasing anyone's peak horsepower. TM is there to prevent the breakage of driveline parts on sudden acceleration.
I have KOOKS and I haven't had torque management since long before their install. I was previously running the Predator performance tune.
I picked up 25 RWHP/ 30 RWTQ with my KOOKS and 3 in x pipe and high flow cats. WIth no tuning.
Then I had the car tuned with the KOOKS and picked up another 2-3 tenths in the quarter mile.
the HP is in the bigger cats and the 3' pipes behind them. headers take a little away down low, but put it back up top. it seems that the QTP complete 3" system would show the biggest results. but with a H/C all headers would shine. cats heat the exhaust gases up to 550 degrees, having a 3" pipe behind allows the gases to expand and make a stronger signal. also the larger pipe gives a place to store the gases, not letting them be sucked back up the pipe. thats where the new found power comes from. i believe you could for get the headers on a non H/C car, replace the cats, and add a 3" pipe HPC coated. you could get the same gains for a lot less money. i think HPC coating the cats would help also, hot gases cool down they slow down act like a plug. magnaflow took a 1985 chev i/2 pickup with a 350. it had dual 2 1/2 in pipes with flowmasters, no headers. they put a complete 3' system on, 3' y, to a single 3' pipe, one cat, three inch all the way out to a three inch magnaflow muffler, to one three inch tail pipe. they got 30 foot pounds of torque at 2500 rpm more than that the dual 2 1/2 system. i have a 1998 with bad cats, i think i will buy 2 1/2 cats hi flow, and a three inch pipe to the borlas. have it HPC coated all the way. also dyno before and after. might as well try thats all a streer can do! sorry to hijack your thread............
Drifting
Joined: Oct 2003
Posts: 1,624
Likes: 0
From: Chattanooga Tennessee
St. Jude Donor '08-'09
I had some Kooks 1 3/4 headers, hi-flow cats, 2 1/2 X pipe to my stock 2 1/2 inch Ti system installed recently.
On the dyno without a tune, I gained 13 rwhp and 8.6 rwtq. I was expecting more, but the car is awesome.
I will say the car has come alive with the headers.
Headers, cats, X-pipe are worth while mods for bolt on sotp power.
augydog
On the dyno without a tune, I gained 13 rwhp and 8.6 rwtq. I was expecting more, but the car is awesome.
I will say the car has come alive with the headers.
Headers, cats, X-pipe are worth while mods for bolt on sotp power.
augydog
Team Owner
Joined: Aug 2003
Posts: 38,314
Likes: 35
Originally Posted by loudsam
I got to thinking again about what you said above EB20003. I've been around here long enough, (as if that should matter), where I feel like I should have every right to say what I feel! BTW, what are "some people" going to DO if they THINK I "imply" something they don't WANT to hear? Maybe it's true, that you think your just giving me some "friendly" advice. But, I'm a BIG OLD BOY my "friend", so I don't need YOUR "help" protecting me from others!
Would another set of headers make him more? I would say alot of the answer to that question would be in the tuner shop and dyno!
At the risk of jacking the thread; How do you like the 3.42's with your t/c? I'm running the 2800 stall through 3.15's and I like it!!! BTW; I was, (more or less), just generalizing with the line you quoted, (that you wouldn't touch). I guess I just meant that you can "jerk around" dyno results quite a bit.
When the same exact points you just made were brought up, about the possibility that dyno numbers can be manipulated, as well as the fact that the results would carry more validity were they "independant" results, at a dyno owned by someone without a vested interest in the outcome, ..... it set off a firestorm. Even if there was no wrongdoing, and no one ever said that there was mind you, the appearance and the possibility, of impropriety, no matter how unlikely one may think it is, should be eliminated whenever possible so as to eliminate all doubt as to the validity of the result.
Sort of like holding a raffle and having one of your family members win it. May have been no wrongdoing, but how does it look?? So you don't let your family members participate.
Mine wasn't an offer of "protection" of you from others.
Some people get real bent out of shape when you imply that their dyno numbers may not be as accurate as they may think. They can get even more defensive when you say that the numbers can be manipulated. Some are very sensitive about that. No one is trying to "protect" you from them , just a friendly note to make you aware that they are present.
I was essentially telling you not to walk into the trap that I did when I stated essentially what you had stated when you said: "I would say alot of the answer to that question would be in the tuner shop and dyno" and that you can "jerk around" dyno results quite a bit. If you consider that "protection" then you are mistaken. I agree.
If you have no problem with possibly offending them by stating or implying as such then thats cool too. I didn't have a problem with it either as I am a BIG OLD BOY myself.
Last edited by '06 Quicksilver Z06; Mar 26, 2005 at 03:31 PM.
Burning Brakes
Joined: Feb 2004
Posts: 831
Likes: 0
From: Country Boys Can Survive.
Originally Posted by EB20003
If you have no problem with possibly offending them by stating or implying as such then thats cool too. I didn't have a problem with it either as I am a BIG OLD BOY myself.
Doug
Would you mind if I posted my sig just one more time? Thanks! I love doing it!