Advice on High Flow Cats

[ken1985]

As many of you know I have a stock 1985 C4. I'm planning have Steve at Bryner install a new B & B stainless steel exhaust system from the converter back. The new exhaust pipe is 2 1/2 inches in diameter compared with the 2 1/4 inch diameter stock system. Therefore new exhaust pipe is about 23% larger in area cross-section.

I'm also going to have Steve replace the 23 year old stock catalytic coverter with a new "super high flow" catalytic converter. Ecklers say it "outflows Stock Converters 80 - 100 CFM To Yield 5 - 10 H.P. Improvement".

I have not changed the intake system except for a K & N air filter with an open lid and moving the intake sensor from the engine area out to the plastic air intake in front of th engine.

My question is will going with the "super high flow" converter cause problems such as loss of low end torque or cause the engine to run too lean, etc.

Should I just install a new converter with "stock" specs along with the new B & B's?

Any advice would be appreciated.

Thanks, Ken

[hcvone]

Ken, you will be fine, you will have enough back pressure, on several of my C4's I removed the cats completely, and a few other I used high flow cats from Random Tech. :)

[Doug Bereczki]

Ken, on my 87 I deleted the cats and there was no loss of low end torque. ;bt

If you want I can dig up my dyno sheets of before and after.

[ken1985]

Thanks guys to the feedback. I just wanted to make sure I wasn't going spend a lot on money and end up with less performance.

Ken