cat convertor

[3.4grandam]

hey guys whats up, i have a question about my 2001 3.4 grand am. iright now i have an exhaust and intake on it and i wanted to no if i took my cat off and replace it with just a straight pipe back to the muffler if it will give me any noticable horsepower. and when i take it off will it mess with any computer sensors or anything.

[Ridenour]

Removing your cat will throw 02 sensor codes; if you were going to remove it completely, you would need to buy a simulated 02 sensor to prevent the codes. Removing it completely will give you a little bit of a cracklier/ricier sound. My advice would be to get a high-flow cat, and then you won't need a sim 02 sensor. Removing it completely or getting a high flow cat will both only get you about 3-4 hp gain max. The stock cat really isn't a flow issue - it's the stock muffler that's so restrictive.