here's my question guys. i want to get the jdm dc 4-1 header but i'm not sure if i should go 2.5" all the way back from the collector or if i should get a donut gasket and do a 2.25" straight pipe and exhaust??? let me know what you all think. i will end up with all skunk2 valvetrain and a 75 shot of nitrous, stock bottom end. thanks for all your responces.

Current mods:
AEM CAI

Future mods:
aem pullies
skunk2 manifold
type r throttle body
skunk2 cam gears
sk2 stage 1 cams
sk2 valve trane
75 shot zex
msd ignition retard
JDM dc header 4-1

 

You shouldn't need anything over 2.25"

 

2.5

 

With basic bolt-ons a 2.25" is all thats needed, but if you are serious about doing all your future modifications (ie. cams, NOS, etc) then go with the 2.5".

 

will it hurt me in the beginning to go with 2.5???

 

I have a 2.5 inch exhaust on my b16.

All I have is an intake and a 8 lb ACT flywheel.


It will hurt low end a little but who cares, you have a b16, it's all about revs.

If you plan to mod it a 2.5 inch exhaust is fine, but only if you plan to mod it.

What are your plans for the car? FI or NA?

 

go 2.5

 

go for the 2.5 since you are on the BOTTLE!...

 

2.5". I lost NOTHING w/ a stock internal one. Gains all across. The back pressure stuff is an old wise tale.

 

2.5