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 claims 503 horsepower in M4 Competition tune, but dozens of easily googled dyno charts reveal the peak power is closer to 550 hp. The torque number seems to be accurate; BMW states the engine ...

This adds a switchable four-wheel drive system to the M4 Competition, allowing you to choose between four-wheel drive, four-wheel drive Sport and two-wheel drive. These come with 20in black alloy ...