Does it fit in a 90 civic Si? I mean the exhaust piping is pretty much identical right?

 

i believe someone did this beofer and it was something like 5 inches too long or so, but its possible, just be prepared to cut and weld a tiny bit not really a bit imo, but then again i have a weilder and air tools for cutting steel so. . . .

derek

 

yes, its too long. prolly too wide as well