[FastFocusZX3]

FI plans for the future though...

 

[tools]

you will actually loose horse power by going to anything above 2 1/2". The exhaust cools too soon and causes lose of HP. Stay with 2 1/4"

 

[FastFocusZX3]

2 1/4 even if I later add a blower?

 

[FastFocusZX3]

This one has been perplexing me for a little while now... I currently have a focussport Race Header and flex-pipe... The diameter of the outlet on the flex-pipe is 2.25 in. would an exhaust larger than 2.25 in. offer any gains? would it offer any gains in a scenario such as adding the "someday it'll be out" focussport supercharger? basicly I'm going to be N/A for the moment, but there is a possibility that someday down the road I might purchase a supercharger (not a jackson) since my flex-pipe is 2.25 is there a point to getting a larger diameter exhaust or not? I've heard time and time again about how a larger exhaust is better for FI and air flow, which makes sense, however it it is traveling through the 2.25 flex first is there a point?

 

[UltegraSTI]

nah, u'd really have 2 b makin sick ponies NA or goin FI b4 u should think of it...and at that u'd need 2 address ur flex as well in an ideal situation. stay at home w/2.25 and u'll b fine. besides from what i've seen all the 2.5s r much louder, dont think w/that race header, that this is what ur lookin 4.

gl,

-Ult

 

[Andy Smith]

Originally posted by tools:
you will actually loose horse power by going to anything above 2 1/2". The exhaust cools too soon and causes lose of HP. Stay with 2 1/4"

<font size="2" face="Verdana, Arial">That's not true. Is there a magical barrier at 2.25 for n/a 2.0Ls? No, a bigger exhaust will always provide you with more peak HP which is why apexi and HKS always dyno higher than other companies (because they use metric 60mm piping) which is bigger than 2.25 inches so you get that benefit. A bigger exhaust will always lose low end, people often just choose 2.25 cause it sits in the middle of losses on the low end and gains on the high end. I'd say a 2.5 inch exhaust wouldn't be that bad on this car, 3 might lose a lot down low, so i'd probably stay away from that. If your doing big power adders I'd say go with one of the 60mm systems or a 2.5 inch. If you decide to go big turbo 3inch or bigger is the only way!