I have a b18c1 block with 00 type r head. i have a 96 gsr header on a 00 gsr cat. i tried using the si b pipe but it came up short. so if i get a gsr b pipe will that work??? (gsr header/cat/bpipe). will it bolt on directly? if not what else can i use???

 

I would just get a custom 2 1/2" B-pipe made. The Si B-pipe is probably a bit restrictive for your setup. As for the GSR pipe, I have no idea if it will fit or not. Good luck.

 

I have an eg with b18c1 so I don't know the specifics about an ek exhaust (i think you have an ek as indicated by your handle), but I do know that the GSR manifold is about 4-5" shorter than the Si, ITR, LS manifold. With the eg you can replace the second part of the gsr manifold with the second part of the si manifold and it lines up correctly with the exhaust. Instead, I purchased the DC 4-1 header for the DC2 ITR and it came out to be the correct length.

I don't think that using the second part of the Si manifold would restrict flow any more than using the GSR second piece. I believe (correct me if I'm wrong) that all b-series USDM manifolds (this may not include ITR, bc I have no idea about that one) have the same diameter collector.

 

Reading over your post again... I believe that if you buy the second part of the usdm manifold from a Si (or use the Si manifold instead) you set up will line up with the catback with no problem.

The LS, ITR, and Si header are appx 4-5" longer than the GSR. I believe this is the gap you are referring to and the reason you are running into problems.

If you plan on doing a catback with a high flow cat I would seriously suggest purchasing a DC JDM 4-1 header (has a 2.5" collector) -- Just don't buy the one for the GSR its too short. It will offer better performance and should line right up.