Originally Posted by Blackedout
Doesn't cattles improve hp and mpg
Actually, catalytic converters are HIGHLY efficient nowadays. Leaps and bounds over what they were in the 70's, 80's, and even early 90's. I believe a few studies were done, unofficially, on our cars that proved you actually lose mpg by removing your cats because of the 3.8's need for that additional backpressure at city speeds.