honestly, there is absolutely no difference that you will feel.

apparently one of them gives slightly better low end torque, and the other gives better power up top. i can't remember which though. it really won't matter, though. the difference will be negligible.

the 4-2-1 is supposedly better for mid to low range and the 4-1 for top end.

Honestly don't get rid of the nismo header. Very expensive and great quality header

thats not a good reason to get another header.b/s chain cut , cams , safc tuned , weight reduction for n/a . but if you insist on buying a new header xs race header is cheap 200 shipped.but it will throw a ses/cel.

ivanv06 wrote:

thats not a good reason to get another header.b/s chain cut , cams , safc tuned , weight reduction for n/a . but if you insist on buying a new header xs race header is cheap 200 shipped.but it will throw a ses/cel.

no it will not. what are you talking about. 02 spacer and you're good to go. takes 30 seconds.

the first time i started my car after putting in the 02 spacer, no light. easy as pie.

i have a spacer.

MySpecV314 wrote:

i need help on a new header...i have a NISMO header that i am trying to get rid of and get a new header...im wondering which header style is better for the performance 4-2-1 or 4-1 ???
i need help so people that own any of these let me know what you prefer

{moved to B15 Exhaust}

4-2-1 Header will give you better low end torque...

4-1 Header will give you better top end...

4-2-1 Header is usually two piece, eliminating stock exhaust manifold and stock midpipe, thus getting rid of both cats...

4-1 Header eliminates only the stock exhaust manifold, retaining the stock midpipe, so that leaves you with one cat...

sharpmaxell wrote:

not again....................................................................................................................

If you have NOTHING to contribute to this thread, stay out of it, please.

atomicguy7 wrote:

If u have the nismo why not just keep it

He has NISMO header with CAT, which is as bad as the stock exhaust manifold with pre-cat...

4-2-1 is better for auto
4-1 is better for manual

I'll put my 2 in this real quick, because I have two different cars, and both are manual and auto.

The Spectra I have when I put my header on and opened up the exhaust wih the 4-2-1 yes i gained a lot more low end torque and Mid range, depending on yoru intake and how you can tune your car you can get the top end to pull too, but that is with an automatic tranny; and now that I own my Spec well the kia is my show car/cruiser.. The Spec has of course way more torque but when I bought the car used it came with a DC 4-2-1 Header (lol and problems, but now I can finally feel the power) But my car has more low-mid range grunt compared to my friend who bought a 4-1 Header for his Spec, where on his top end especially when the secondaries open he has more pull..

So yes there is a Difference, as in the ranges power ratios between cars, there are a lot fo factors to consider but don't for get when testing on dynos how the knock sensor retards/advances the system too, which can make a difference. (And you can tell some times your car seems fast others it just seems like erm ok)..

Either way they seem the same it just depends on what your tuning for as the specV has massive torque, but you can still tune the car to work with you on top end as well thanks to the secondaries and depending on air intake set up..

Oh and if you have an 02-03 with same year tranny still and your friend has a 04-06 or even a newer tranny then yours with 04-06 He is going to pull on you because your gears are shorter taking off but longer after 3rd, while his gears are shorter, and final drive is longer (So he is going to pull on you)

My friend pulls on me for that reason, he has replaced 04-06 in his 03..Gearing Table of why th e04-06 is better

Albi

Last edited by GSXellence (2008-12-10 11:59:26)

No affence but if your friend has a spec and he beat you mabey its just your driving? And every engine is made different in a way.

If you have the Nismo With the Cat get it off ASAP. Other than that a header is a header. I personaly want a 4-2-1 DC Sport Header I dont want any cats, more power IMO but who am I. LoL
-actually if you have a cat on your header that will not give you the gains that one with out will. This stuff is every where just look it up.

get a 4-2-1 IMHO is a better desing for the QR25  that's what i have and i love it

MySpecV314 wrote:

atomicguy7 wrote:

I've heard that the 4-2-1 is better but IMO i didnt feel a difference. If u have the nismo why not just keep it

well my friend just bought the same exhaust that i have and a 4 2 1 header style for his bone stock spec v  and he beat me by like roughly a car and i have a cold air nismo header and a exhaust but a stock down pipe and it pissed me off so now i want a whole new header but idk it might be cause of the down pipe being shitty...oh and i have a big exhaust leak in it too

driver mod anyone?

gut your nismo you'll notice a bit difference and you wont spend money unneccecarily

it really does not fucking matter for what you want to do with it. i doubt youre going full race so again, it doesn tmatter, just pick one that you like and thats in your price range and buy it