'03 no cat question? thanks

[kschif1]

A few years ago my magnaflow muffler rusted out so I simple cut it off and welded a pipe to fit perfect so it is a single pipe to the rear as it would seem stock. The sound actually isnt bad. Some close friends who are all into racing bmw's and have some Fx4's have been trying to talk me into cutting my cats off and keep it open. What are yalls thoughts on this and would it hurt anything. Will the sound difference drastically increase? what are the + and -'s of this other than sound difference.

Thanks,
Kenneth

[1988 GMC 355]

No point in cutting them at all, keep them. Nothing will be gained what so ever.

[Rye 21]

The only reason to get rid of them is if you run LT's and cant fit them, but cutting them out on a truck with stock manifolds is dumb.


If you do cut them out, do not get rid of the two (front) O2 sensors, your truck needs these. You can delete the rear O2's, and it will be ok, but your CEL light will be on, and the truck might run rich.

Things done to BMW's dont apply to fullsize American trucks