Bypass the cat?

[Mean Green]

Originally Posted by cleverklutz

To an extent if you remove restriction from the intake, the head, or the exhaust you'll pick up "free horsepower." An engine is often compared to a big air pump, make the air go in, through, and out easier, you'll improve efficiency.

I previously had a 1993 Dodge Dynasty with a 3.3L engine. I put in a test pipe, removed the muffler, and ran a 2 1/4" diesel resonator. I gained a second in my 0-60 time. My brother has a 1994 New Yorker. His trip computer showed he gained 2 mpg when he pulled the cats out of the exhaust.

I'm thinking there are gains to be had on my car pulling the cat. Keep in mind mine is N/A tho. I'll check into the bylaws here, and if it's all good I'll try it.

Ben

Keeping in mind the na is only 150 hp that weighs 3200 lbs removing the cat for a test pipe will likely gain you a whopping 1-3 hp that you'll never feel. It's also been said that the stock cat flows pretty well on the na and the exhaust system is all mandrel bent so it flows well for a na car. I went through all that adding an intake, header and an exhaust system on my '01 PT. Though it felt faster to me when I put it back to stock it was just as slow. But, building up a car is fun and as long as you don't expect big things out of the na PT then it should be all good. When I started modding my '03 PT GT that car took well to new performance mods. Got it up to 280 hp and that little car was fun to drive. Enjoy.

[05CruisergtHO]

My previous car was a 2002 dodge neon 5spd with an aem intake, energy motor mount inserts, ported TB, ported intake manifold and a MPX underdrive pulley. Finaly I added an OBX ceramic coated header/test pipe. The sucker was loud and anoyying on the highway. I did see better gas mileage and more performance. But personaly, I would just go with a high flow magnaflow cat or even a catcocat ( I hear they are the best ) with a turboback exhaust.