If you're doing a whole driveline swap I guess clutch and diff failure arent concerns. You can get a w201 down to 2500lbs, fit a 16x7.5 in the stock fenders, and have an awesome rear suspension that people have put a lot of power through. Id imagine that if the car could stay together with various modifications youd have a burnout machine around 350-400hp. I have a friend with a turbo m50 e30 that makes about 450 and its basically useless at anything but highway pulls and he's still wanting more boost and a wide body.