would an exhaust from a 90 240sx fit onto a 94 sentra? what about just the catalyc converter? i need a new catalyc converter and was wondering if i coudl take it form a parts car 240 i have, but i figured if the exhast fits, y not put the whole thing on? also, ive never done exhaust work, but is it all bolt on? or do you need to weld it on? any help would be much appreciated. thanx.

A 240 exhaust bends differently, so no it wouldn't work on a sentra. Stock exhaust systems were bolted on from the factory, but the problem is after many many years, those bolts have rusted to the point of seizure. So you would probably have to cut it off then re-weld it on. But why not just buy a high flow catco converter off ebay. The cat on the 240 can't be in any better shape than the one on the sentra.