I just patched a hole in my exhaust (ahead of the pre cat) and boy what a difference. Not only is it a smoother, richer sound (not to mention quieter), but there's a lot more giddy' up in the bottom end. Now the trick will be to find a way to have stock back-pressure at lower RPMs, and free flowin' exhaust at higer rev's. Any ideas?

 

I take it you have an NA. They make RPM switches(I believe MSD makes one) so you can have your aux. ports activated. Look at www.fc3s.org for a writeup I believe.

 

That's great for the intake. In fact, I've got some ideas I want to try for that. I was talking about the exhaust side though. No aux exhaust ports on these things.

And yes, I've an '87 NA.

 

Are you looking for something that is tunable? If you are looking for something that you can set for street use, and that you can change for when you want to race or what ever, you could get a tunable super trap. What exactly are you looking for along the lines of free flowing?
Charles

 

I was thinking of a full dual exhaust (with cats and mufflers) but with takeoffs ahead of the cats dumping into straight pipes all the way back. The straight pipes would have some sort of flap or valve assembly to prevent them from being used below a certain RPM, but would open up by solenoid at the ideal RPM. Actually, It would probably be better to run the street legal portion from the take-offs and still close the straight pipes. I'm sure it's completely do-able, I just have to find/design the components. What I'm looking to do is further linearize the power output. Of course, a tunable exhaust may be a better bet. I want this to be a very capable street machine. I want it all, all of the time. Compromise is evil. I'm just looking for every way around every problem right now, so I can build the perfect system.