Related: 2025 BMW M4: New Tech, More Power ... the engine stop-start system and provides an additional nudge when the car first begins moving. The 430i makes 255 horsepower and 295 pounds-feet ...

The resulting car would be slower in a straight line than what CarBahn has built. But who cares? Finally, the brakes. We stopped the CarBahn BMW M4 from 60 mph in 89 feet. The GT3 needs 93 feet ...