With 735 horsepower and a Dinan-tuned suspension, the CarBahn BMW M4 is a precision-guided sledgehammer. Okay, so what the hell is a CarBahn? And what does it have to do with this $135,000 ...

BMW E60 M5 Dinan 5.8 Stroker in Colorado boasts 142,000 miles and a rare Dinan conversion from 97k. With HRE wheels, Brembo ...