[FTI-EDC]

Originally Posted by MellowYellow

So what do yall think Headers for an L99 Automatic.....1 7/8 or 1 3/4 ?

I have always been told that on a heavily modded car go with 1 7/8 otherwise especially on an automatic go with 1 3/4 thats mainly stock go with 1 3/4.
Because the 1 7/8 will hurt you in the low end on a basically stock car.
meaning a car with exhaust , headers , cai and a tune.

We have seen ARH's #'s for the LS3 with 1 7/8 has anyone put on some longtubes on a Automatic and what #'s did they get and what size headers did they get?

I was going with kooks however the only way for me to use my borla axle back would be for me to go wtih ARH there xpipe bolts on to the axle back from borla.
Kooks Xpipe only bolts on to there mufflers so with using there headers i would be forced to have bought there headers , connection tubes and there mufflers I couldnt use there set up with borla.

kooks said go with 1 3/4 for an automatic ARH says 1 7/8
kooks said 1 3/4 would be perfect for my car 1 7/8 would hurt it in the low end.
ARH says on a LS3 go with 1 7/8 and the same would work for a L99
however I dont see any numbers for a L99 yet from ARH.

What are yalls thoughts and info??????

Is there anyone who has put a set of 1 3/4 longtubes on a L99 with a 3inch xpipe and a tune and if so what are you #'s now ?
What were they before and after the tune ?

Some pretty good header discussions