hamster

Anyone have any idea about the expected horse power gain using an exhaust with a single gutted catalytic converter and a stock muffler?

the car is a gsl-se.

My guess would be around 15% gain. That would mean around 130 hp at the wheels. Does this sound right?

Gregs

15 percent froma guttet cat?, i highly doubt that...
maybey from a header, but not a guttet cat

hornbm

Well I have the stock GSL-SE exhaust, I cant see much of a performance increase, but one thing is for sure, the car sounds like a freaking honda now.

I gotta get my new exhaust on, my current setup is horrible. DONT gut those cats man, unless you like the crappy tinny sound of a honda.

Bass

I would think that your gain would depend on how much your cat was clogged. But I must admit that your 130 hp at the wheel is a little too hopeful.

hamster

thanks for the input


I am guessing 130 at the wheels with this argument.

Racing Beat claims that their exhaust (header with single outlet) will increase horsepower about 22% at 7000 rpm.

They then claim that 2/3 of that can be achieved with only the cat replacement pipe.

2/3 * 22% = 14.6%

I figure that a gsl-se gets around 130 at the fly wheel and will lose near 15% through the drive train. So with the gain from the Cat replacement pipe you get 130 horsepower at the wheels.

It seems to me that the gutted cat is at least similar to the cat replacement pipe.

I am not interested in the sound.