mrstarr

Cool, thanks, found them: http://www.summitracing.com/search/?keyword=exhaust+cutout&page=1 I didn't know such things existed. Now I just need to pick the one that would fit my 280zxt.

I had this idea for a mod, that when you are racing, you could pull a hood latch type pull under the dash, which would open a big valve inline on your exhaust pipe system to vent your exhaust right below the engine direct to atmosphere (straight down and out). For daily driving, you leave it closed, but in those rare situations when you wanted your exhaust to flow unrestricted, you could open the valve and exhaust would be directed down and out directly below the engine. It could still go out the back end, but most would follow the path of least resistance out the valve opening much further up the exhaust pipe. However, I noticed something today. The 280zxt doesn't use the WOT Wide Open Throttle sensor on the TPS, so you've got a perfect little switch already built in, that you could simply wire up to a solenoid in a very simple circuit, to open and close your hand-made exhaust bypass valve automatically for you. When you punch it and are wide open throttle, the WOT sensor switch closes, which would activate the solenoid, which opens the valve and exhaust goes right out the exhaust pipes below the engine with the least amount of resistance, without having to travel all the way to the back of the car through the cat, etc. As soon as your throttle decreases the WOT sensor opens, the solenoid loses power, and a spring closes the valve back to the default closed position and returns things back to normal. Your car of course would all of a sudden get very loud when its at wide open throttle, but I don't see this as necessarily a bad thing. Of course I would have to fabricate this little valve gizmo but it doesn't seem terribly hard to do. I don't have to pass any emissions requirements, and I'm not an exhaust expert, but is this a stupid idea? It seems to me an engine is nothing but a huge air pump, and the faster you can let it move air through it at high rpms, the better. My exhaust is 100% stock, so this seems like an interesting alternative to replacing it all with a 3 inch pipe. Which I could do as well.