LilCivic04

i have a fully built d16z6 and will be going equal length manifold and a gt28rs turbo. at the moment im running a 2.5inch catback exhaust and im planning to get a 3 or 2.5 inch downpipe. would i gain anypower doing 3inch downpipe to 2.5inch exhaust than doing 2.5 all the way? i just dont want to spend any money on exhaust at the moment because mine is fairly new. if i would have known i was going to turbo my motor before then i would have went 3" all the way back.


Modified by LilCivic04 at 10:41 PM 10/26/2005


Modified by LilCivic04 at 10:41 PM 10/26/2005

abnaasefmb

just make it a 3" and use a 3" to 2.5" reducer. you can cut it out and go full 3" later if you want.
and one thing to keep in mind if your going to go with a gt28 that you probaly know already. you can get the gt28 with a t3 flange, its called a t3 drop-in. there is a lot more manifolds and down pipes out there for the t3 finding a set up for the t25 is a lot harder. i wish i did more research on this before i got mine. good luck.

i'm not trying to pimp any company but ATP turbo has the 3-2.5 reducer and lots of other gt turbo stuff piping and bends.

LilCivic04

yes i know atp has the t3 drop in, thats what i got. anyone else? will there be a BIG power difference running 3"dp and 2.5 exhaust instead of 3inch all the way?

LilCivic04

ttt

Blackack26

will you gain power? yeah

will it make a big difference? doubt it

LilCivic04

is it a bad idea or should i just run 2.5 all the way back?

1boostedcivic

the power difference is un noticeable. but if ur turbo is really big, go 3 for spooling issues.

tony n.

3" all da way

Boosted Power

I agree...3" all the way for your exhaust system. You really don't need back pressure unless you're running naturally aspirated.
2.5" and 3" will be very noticeable. It will open up your exhaust and let your turbo get rid of the gas faster...wich = more hp/tq.

fjt

I have a flared test pipe 3" - 2.5" if you want it let me know..