In Reply to: Re: Straight exhaust posted by Mark Reitman on September 27, 2000 at 17:34:22:
Hi there folks, I'd like to run a straight exhaust on my 90 e30m3.
I was wondering if you know of anyone out there that makes such an item.
I saw some korman sport systems, but I am looking for something cheaper and less permanent.
Oh quality, but straight.
ps-Would you trust someone to fabricate a header back system?
The E30 M3 actually runs best with the stock exhaust. The motor was built to run with some back pressure and by opening up the system, you will actually lose some low end and midrange. Unless you change your entire exhaust system from the headers all the way to the tailpipe, the best bet for a street driven car is to "Leave it stock." We have dynoed and drag raced the E30 M3 as well as tracked the car, and our results always lead us back to the stock muffler for the best overall street performance. If you want more horsepower, go to a chip. such as the autothority and run 100 octane racing unleaded gas. Our stock
authothority chipped, stock muffled 90 M3 ran consisten 14 second quarter mile time with 0-60 times in the mid to low 6's. Changing your exhaust on this motor will actually cuase you to reduce torque, which this little motor needs more of. All a straight pipe will do will cause your car to be louder and this will make yor think that you're going faster. The E30 M3 needs backpressure to run at peak street performance. Unless you run complete wide open throttle, such as on a race course, a straight pipe will cause you nothing but greif on a street driven car. Unless you see the dyno sheets of someone who runs an open pipe and know what modification have been done to their motor, my adivse is DON"T DO IT! Your ECU will have great difficulty unless it has been properly reprogrammed for this change on a street car.
WHAT CHIP IS THIS? AND WHERE DO I GET ONE.. YOU SAID AUTHORITAVE CHIP? AND THAT IS WITH VP FUEL? OR 100 OCTANE..?? LET ME KNOW ASAP..