Hello, just looking for some input from anyone who might be more experienced then me about this. If I have and ECU tuned for say Intake, Intercoolder, Dp, Mp, and exhaust would i see any problems from say having the stock cat still on untill i purchase a Hi flow one?

 

Should be OK. Might run a little rich, but shouldn't be a problem.

 

ya thats what i was thinking, but with my luck there would be a giant unforseen problem if i did ask heh.