I have a borla cat back exhaust system, and i want to get a new cat converter for it..... i believe the piping on the borla is 2.25, and i was looking at different magnaflow cat converters.... would any of them work? if not which ones would work? I saw a different variety of the sizes and shapes.... do they matter for performance or fitting? Also i noticed that some of them say "with air" or without air....
what difference does that make? I would appreciate any kind of help.....
Thanks,
Shane