aftermarket header

[b18a1crx]

hi. i have a 91 crx si with a 91 b18a1 motor. i was wondering what header would have more horse power and or if it would fit?
a 90-91 header or a 92-93 header? i know on a stock motor the 92 and 93 b18a1 have like 10 more hp. im kinda new to this website so any help would be appreciated

 

[CAFROG]

Not in the stock OEM exhause manifold.......I believe its in the head or IM.

If you want performance..... a stock LS exhaust manifold will not be worth your time.

Many people say good things about a tri-y header. Many companies make replicas of these now (since the technology is kinda old) so they aren't too expensive and have quality welds.

 

[b18a1crx]

thanks for the help ill look those up

 

[78civic]

The 4-2-1's usually give the better all-round performance.
Like on the early 90's accords, tegs, and early RS civics the 'stock' 4-2-1's always gave better hp #'s (for basically stock configuration)

What's on the car now?
If it's just a street car, with air, stay with the 4-2-1 for the torque gains.
I think that the different years had different mounting points and clearances under the oil filter, trans linkage and length before the 'doughnut' collector.

E

 

[b18a1crx]

its has the stock exhaust manifold on it now. it has a bosal cat-back on the back half.
just wanted somthing to add some hp and some tone to it.
the stock manifold is a 4-1 i think. u think the 4-2-1 will be louder?
yeah it is just a street car.

 

[CAFROG]

4-2-1 isn't necessarily louder but better mid-range performance. I feel 4-1 is top end