4-1 or 4-2-1?

[badnan]

someone said that the 4-1 headers are best for the gs-r, what about 3rd gen rs/ls/gs? should i go with 4-2-1 or 4-1? i was looking towards 4-1 cuz they slightly cheaper but i want the best performance. oh yeah im going n/a (maybe in 9 months ill have enough for a supercharger). all i have right now is a cai, i plan to get headers soon.
thanks

[M-type]

well, right now, in your case a 4-2-1 cause your power is in the lower rpms. The vtech engines gets a big boost with 4-1 at high rpms. To tell you the truth, integras have one of the best stock exhaust manifolds, so unless you boost it, you dont need to get headers. If you are absolutely sure about the supercharger, get the 4-1 which will help you out in hi-flow situations. If you do get the sc, i suggest getting a light weight fly wheel and a stronger clutch, you can 'chirp' going from 2nd to 3rd.

[badnan]

yeah my plans are simple i/h/e then cam gears, underdrive pulleys, clutch, flywheel, probably fuel rails and fuel regulator.
then if i feel i still need some more ill go supercharger

are you saying that getting a header will not increase performance that much? ive been told to expect ~15hp from i/h/e. would i get the same ~15 if i just did i/e?
thanks

[00GSR]

Originally posted by badnan
someone said that the 4-1 headers are best for the gs-r, what about 3rd gen rs/ls/gs? should i go with 4-2-1 or 4-1?

You redline at 6800rpm, so go with the 4-2-1. The 4-1 is designed to make power over the 4k point in the band, so it benefits the high revving, Vtec, B18C engines...

[M-type]

15hp? it all depends on what intake and exhaust you get, (running without boost) you just have to mix and match them.

[badnan]

well ive already got the aem cai, going to get the dc ceramic 4-2-1 headers, and for exhaust im looking at the dc sports catback,greddy sp and just maybe the apexi ws(porbably not tho)

[JD@af]

You have made the right decision - you should be getting the 4-2-1 with a B18B. However, B18C1 or not, I want to make sure you all know that the regular old DC Sports 4-1 header is a bad idea for any B series engine when supercharged (I know, I had a DC Sports 4-1 with a JRSC for several months). The 4-1 features semi-narrow, long primaries, that merge just before the cat.

With supercharging, where it is very important to keep the exhaust gases moving and preserve their velocity (which is in part due to the fact that Honda uses smaller diamete exhaust valves than intake valves), you want primaries that quickly branch into wider pipes and feature "steps," to dump those exhaust gases very quickly. The DC 4-2-1 does this pretty well; the 4-1 is terrible in this regard.

There is the DC Sports JDM ITR 4-1 header, which is a horse of a completely different color, and is just about the best mass-produced header available for supercharging a B series engine.

Just wanted to make sure that no misinformation was distributed here.