I searched for "differences" and got @143 topics and not one was really helping. Reason I am asking is I have a 91-DX and eventually will swap it, but for now I want to put a cleaner exhaust on it, like the factory b-pipe and an add on rear section. Well all the manufacturers for exhausts that fit the 91 hatchbacks all label
their exhausts to fit both the DX and the SI, (cat-back) but Honda lists two different part #s for the b-pipes. I think the difference is in the diameter only. If anybody knows please help me out and let me know, Thanks