dayton, tsai came out with a pipe for the HPI Savage that was totally trick and realistic. My brother in law bought if for more bling-bling ... it made no noise and was a bit slower.
The thing with the tuned pipes is that your engine's exhaust are actually like pressure waves that shoot through the fat part of the pipe at the speed of sound. And then bounces back to the engine to pressurize the cylinder. If you increase your stingers length, you take away some or even a lot of RPM. If you cut it shorter, you increase RPM.
It's not scale-looking with a stinger coming out the side of your body, but it make the car work.