1 3/4 Header vs 1 7/8 Header
Le Mans Master
Joined: Oct 2007
Posts: 6,149
Likes: 11
From: Greater Detroit Metro MI, when I'm not travelling.
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
I'm sure they do great against your 1 3/4 but can you please post some of these dyno results or track results instead of just the peak power. It would be helpful to see the curves and existing dyno's can be misleading.
Do you have a comment on GTOdoug's results posted in this thread and would you be willing to make me the same deal as LG did when I bought his headers? If I as a supporting tuner get a gain, I will keep them and pay for them. If not, I wont post the results and you take them back for a full refund. I have no agenda other than I want my car faster. I run 1 3/4 LG's with cats and would want cats on the 1 7/8.
The ZR1 is a 6.2 liter with a S/C not a stroker N/A. My car is a 6 liter making far more power than a ZR1 so they should work on my car big time.
Do you have a comment on GTOdoug's results posted in this thread and would you be willing to make me the same deal as LG did when I bought his headers? If I as a supporting tuner get a gain, I will keep them and pay for them. If not, I wont post the results and you take them back for a full refund. I have no agenda other than I want my car faster. I run 1 3/4 LG's with cats and would want cats on the 1 7/8.
The ZR1 is a 6.2 liter with a S/C not a stroker N/A. My car is a 6 liter making far more power than a ZR1 so they should work on my car big time.
It's not like on a stock ls-2 where you see some lost low end. IMO the better heads and slighlty larger bore on the ls-3 like the 1 7/8's.
I'm posting two ls-3's with 2 brands of 1 3/4 on the same dyno then one
with 1 7/8's. Study them and see which looks better, Gets better for 17/8's with the S/cing !
http://forums.corvetteforum.com/c6-t...s-and-vid.html
http://i81.photobucket.com/albums/j2.../Dynosheet.jpg
Le Mans Master
Joined: Aug 2008
Posts: 5,578
Likes: 61
From: Austin TX
If you switch them? You wonder why you wanted so long!
It's not like on a stock ls-2 where you see some lost low end. IMO the better heads and slighlty larger bore on the ls-3 like the 1 7/8's.
I'm posting two ls-3's with 2 brands of 1 3/4 on the same dyno then one
with 1 7/8's. Study them and see which looks better, Gets better for 17/8's with the S/cing !
http://forums.corvetteforum.com/c6-t...s-and-vid.html
http://i81.photobucket.com/albums/j2.../Dynosheet.jpg
It's not like on a stock ls-2 where you see some lost low end. IMO the better heads and slighlty larger bore on the ls-3 like the 1 7/8's.
I'm posting two ls-3's with 2 brands of 1 3/4 on the same dyno then one
with 1 7/8's. Study them and see which looks better, Gets better for 17/8's with the S/cing !
http://forums.corvetteforum.com/c6-t...s-and-vid.html
http://i81.photobucket.com/albums/j2.../Dynosheet.jpg
Having said that, a page back or two I gave a math formula that shows that a 6.2L engine using 1.875" headers would prefer a 4700 rpm torque peak. It appears by looking at all three dynos that the torque peaks are right around 4600 rpm. So there may be some truth to a 1.875" header working as good or better on a 6.2L LS3. Something to ponder.
Le Mans Master
Joined: Aug 2008
Posts: 5,578
Likes: 61
From: Austin TX
Melting Slicks
Joined: May 2004
Posts: 3,017
Likes: 2
Just to add mud to the water, my dyno sheet that Blue keeps referencing was with stock air intake, and stock, (non-Npp) mufflers..I went 424rwhp..Add say 8hp for Killer bee air intake, (Tom usually gets 10-12hp from it), and 5hp for the Catback.and 5 for no cats .and you get 424+8+5+5=442..
Thread that got all this going:http://forums.corvetteforum.com/c6-t...s-and-vid.html
My dyno sheet:http://i81.photobucket.com/albums/j2.../Dynosheet.jpg
So was it the headers or the other mods? I plan on going back to Toms and have the car re-dyno'ed now that I have Z06 mufflers, and a K&N intake just to see what difference they made.
Thread that got all this going:http://forums.corvetteforum.com/c6-t...s-and-vid.html
My dyno sheet:http://i81.photobucket.com/albums/j2.../Dynosheet.jpg
So was it the headers or the other mods? I plan on going back to Toms and have the car re-dyno'ed now that I have Z06 mufflers, and a K&N intake just to see what difference they made.
Le Mans Master
Joined: Nov 2003
Posts: 8,308
Likes: 157
From: NJ
For those into drag racing.
Again, the 1 7/8 headers seem to be working well for the drag strip on c5/c6's.
We have seen unusually high mph's lately(this season). All the cars have 1 7/8" headers which prove that they work on the strip.
Understood these are not controlled experiments.
I have been around the strip ALOT over the past 5 years studying vettes(c5/c6) and believe the 1 7/8" header may have a performance advantage over the the 1 3/4.
We just swapped out a set of 1 3/4 - 1 7/8 on a supercharged c5 and he picked up an average of .2 over numerous passes in the same air/track conditions.
Controlled experiments are great, but often they are not real world experiments. Every thing that happens on a dyno does't always translate to the strip.
For track results the only real way is to swap them at the track quickly with an automatic that is very consistent.(which can be easily done if some really wanted to).
I can only give people a "strip" educated opinion from closely following modded vettes over several years.
Again, the 1 7/8 headers seem to be working well for the drag strip on c5/c6's.
We have seen unusually high mph's lately(this season). All the cars have 1 7/8" headers which prove that they work on the strip.
Understood these are not controlled experiments.
I have been around the strip ALOT over the past 5 years studying vettes(c5/c6) and believe the 1 7/8" header may have a performance advantage over the the 1 3/4.
We just swapped out a set of 1 3/4 - 1 7/8 on a supercharged c5 and he picked up an average of .2 over numerous passes in the same air/track conditions.
Controlled experiments are great, but often they are not real world experiments. Every thing that happens on a dyno does't always translate to the strip.
For track results the only real way is to swap them at the track quickly with an automatic that is very consistent.(which can be easily done if some really wanted to).
I can only give people a "strip" educated opinion from closely following modded vettes over several years.
Last edited by robz; Dec 6, 2008 at 09:53 AM.
