what kind of gains can you get by cutting off the cat?

 

If you have one of those horrible pellet-bed cats, yank it out by the roots and fling it as far as you can.

Later model monolith brick cats aren't as bad. Quite often, lack of performance is caused by wimpy cams, constipated heads, and emissions-oriented carburetors. What kind of car do you have? What's under the hood? Not all engines will wake up the same from removing a cat.

 

It's for my firends car he as a 89 rs with a 350 tbi.