Oldsilverback

The PO of my 1986.5 has modified the exhaust. It has high flow cats and two straight pipes to the exhaust. It is LOUD!! I love it but my wife doesn't like it- it is pretty loud while on the highway. I spoke with a buddy and he felt there wasn't sufficient back pressure for the engine and that could damage it and was likely contributing to higher running temp. Any input on this?

I have the original muffler and was thinking of having it put back on. Anyone suggest another good option for reducing the sound without going to the full OEM muffler and not breaking the bank?

Thanks for any advice and direction.

Mrmerlin

Post pictures of the parts you do have for guidance on what to order,
call 928 intl and order the parts you dont have and install the factory system

V2Rocket

never listen to this person again.
cut off all communication or better yet, move to the opposite side of the earth.
you don't need that kind of stupid in your life.

backpressure is ALWAYS bad and needs to be minimized as much as possible, but any decent change from the stock configuration of parts needs to be accounted for in the engine's tune.

with the opened-up exhaust, its quite possible that your car is now running lean which can significantly raise the running temperature.

davek9

As its an 86.5, you could add two stock (or GT) resonators after the Hi-performance CAT's depending on how the custom setup was built,
Post up some pics of what they did under there.

Dave K

Oldsilverback

Just to follow up- I ended up putting the OEM muffler back on. The sound is pretty mellow but I can hear my phone and my wife enjoys driving with me. Thanks for the advice and suggestions- much appreciated.