Whut up yall..wonderin if anyone could help me..I have an 01 gsr and I wanted to know what part of the stock type r exhaust bottle-necks? I'm pretty sure the piping size is 2.25, but Im not sure. Would I be able to buy a type r b-pipe and but on an hks hiper rear section? thanks..

 

the bottle-neck is where the b-pipe meets the cat. there's a small section (about 2inches) where the pipe closes down half an inch. I run stock exhaust and I and many others have brought their ITR b-pipes to muffler shops to get the bottle neck out; just cut it off, and have a new part rewelded back on that's larger. I've heard of 2 other bottle necks in the piping but I consider them minor. I beleive there's a couple pics of it too from a couple months ago. do a seach, I'm sure you'll find it.

also add a high flow cat or test pipe, that's a common ITR bottle neck too.

not sure about matting the ITR b-pipe with a HKS hyper axle back. make sure the flanges meet at the right place. IMO, screw the ITR b-pipe and run a 2.5" inch custom exhaust piping to your muffler. hope this helps.

 

sounds good..thanks for the advice