I'm thinking of removing the cat on my car but I was wondering what you guys think.Ive got a stock 305 with 169,000 miles on it.Right now its got a hiflow cat with 3in pipe to a flowmaster 80 series.Would I be wasting my time if I take the cat off?

 

You got a high flow cat... theres no reason to remove it. Leave it on and stay legal.

 

/\Damn you're probably right...better judgement wins again!

 

It's a felony in California to remove the cats. We have guys here in Southern Cali making from 360whp-403whp with cats and all the smog equipment hooked up. This should change your mind or anyone else about removing the emissions equipment.

 

I had the same engine you have in my 1986 Camaro Z28 and I tried all the options: Stock Cat, Hi-Flow Cat, and No Cat, and I didn't notice much of a difference at all between Hi-Flow and None at all. Leave it on.

 

Since my (idiot) PO has both gutted the muffler and replaced the cat with a straight pipe .. that is SMALLER than the stock exhaust diameter ... i'm guessing that this actually hurting performance.

To fix this I have decided to keep the stock headers and Y pipe and go for a Magnaflow cat back, the questions are:

1. which high flo cat?
2. what else will I need to connect all this together?

Thanks in advance