I know Stebro makes an exhaust system for the 90, sedan, coupe and every other Audi made. I really like the system I got for my 90Q Sport. The center section runs $275. and the rear $290. It is shipped with hardware and ready to bolt on, It took about 2 hours for me to complete the install. You can check them out at : http://infoweb.magi.com/~andypet/sthpct.htm Scott 95 90Q Sport