I just need to know if the bolt pattern is the same on the head for the b18a and the b18c.
Later,
BR
don’t have a direct answer but…
my DC Sport 4-3-1 ceramic coated 2 piece header is made for a 92-93 Integra LS and GSR. The part numbers are the same too. I’m guessing it would work for both, thus it should bolt up the same to both. The box actually has a sticker that says:
Acura Integra 92-93 LS
Acura Integra 92-93 GSR
hope that helps a little =O)
http://hybrid2.honda-perf.org/tech/b20/b20dyno.html
the guy there bolted up a gsr exhaust manifold to a b20. It should work.
I believe all b-series header are interchangable it the cat flange that is different. Like the 90-91 Header and 92-93 Header the difference is the down pipe length
Does that mean a 90-91 DC Sports header won’t exactly fit a 92-93 model. I don’t mean just the head bolt pattern, I mean in all respects.
I believe the 90-91 downpipe is different, and won’t bolt up correctly to 92-93 exhausts. But an extension should work fine. Those are just an extra piece of piping you can get welded on at a muffler shop for cheap.
I know for sure the 94+ headers all have too short of downpipes and won’t reach the cat (i’ve tried).
but they will bolt fine to the head.
yes the bolt up pattern is the same…and i got my extension done for like 20 bucks because i had a 92 header on a 91…hope it helps…
later,
Dan 
jonsteR & punk749 - Thanks, that is exactly what I was looking for. I just needed a verification on it.
Blizzard - The G2 GSR has a different head than the G3 GSR. The G2 has a PR3 head and the G3 has the P72 head. The intake manifold bolt patterns are different on the P72 head than any other honda head out there. That is why I wanted to make sure on the exhaust side…
Later,
BR
Originally posted by Blizzard
my DC Sport 4-3-1 ceramic
That must be 1 fugly header 
Originally posted by notecLS
[B]
That must be 1 fugly header [/B]
damn, lol, i mean 4-2-1