How much HP gain I can ecxpect from GReddy catback exhaust??
Maxima 99.

 

2,if not that

 

are there any other system which gain more power than greddy??

 

i've heard you get like ~6-8hp from the b-pipe alone because you are opening up .25" (if you go 2.5")... and the muffler you will get ~1-2... that's what i've read, the butt dyno thinks a bit less... but i can't really tell anyways... it's louder definately

basically a 2.5" = a 2.5" pipe... so why would a system be a significant amount more or less than the other?

y-pipe = significant power increase... can't tell if you have one, you have no homepage or mod list...

 

I have y pipe