I have an 80's Classic....The Porsche 944 Turbo. The 1980's turbo cup cars were producing 250 bhp and had uprated suspension and brakes, anti roll bars etc but were basically the same as the 1988 on production cars. My car has a stroker motor to 2.8 litres ( 2.5 was standard ) is is dyno tested to put out 422bhp. It was built by Promaxmotorsports in the UK, I bought it in 2004 and had been featured in 2 prominent UK porsche mags.
Video of 944 turbo cup cars in action!
And a pic of my 1989 Porsche 944 Turbo