I intend on purchasing some headers for my D15B7, and i had wondered about some exhaust theories. 4-2-1 is supposed to be better for low end mid range power, and 4-1 is better for high. now, im not entirely too impressed with either on my car as of the moment. (its still mostly stock) high end sucks the most, and im wondering if using the 4-1 would hurt low end to mid, or leave it untouched. vice versa as well, do 4-2-1 hurt high end? another question is, what header performs best in the given fields, and is of excellent quality? lastly, i have a stock exhaust, would i even feel the upgrades w/out an aftermarket cat/cat-back? thanks for your time.

 

First off, you don't purchase "headers" for your car, you purchase "a header." Yes the 4-2-1 design is geared more toward midrange power and the 4-1 is geared to high end power. A good header will not hurt performance at any point in the power band (though there are a lot of poorly made headers that will hurt you in places). I'm not too sure about which headers are the best for D series motors, but check out Bisi headers or Bisimoto (I can't remember what exactly he call it). And upgrading the header will not do much for you without an upgraded exhaust.

 

lol, yes, i meant header...back in the day with me it was engines with headers. not so much these days. thank you. Bisi...is he the one who created a 9 second B15 civic?

 

wait still, does having a 4-2-1 hurt upper power and vice versa?

 

bump

 

A 4-2-1 will not hurt high end performace compared to your stock header, but it wont produce the gains most 4-1's will up top. The 4-1's seem to vary, some wont hurt your low end but these tend to not produce as nice of a gain as some that usually cost you a few hp at the bottom. Either one will be better than your stocker.

 

thank you, i think ill do the 4-2-1. Anyone have any brand recommendations?