Beautiful Garage kept 2001 M roadster Prior to 2001, the M Roadster (built 1998-2002) was powered by the E36 M3's 3.2-liter inline-six that produced 240 horsepower - a healthy increase over the already potent inline-six upgrades in the non-M Z3. For 2001, however, BMW went from healthy to insane, swapping in the then-new E46 M3's engine, which in the M Roadster would produce 315 horsepower made at a screaming 7,400 rpm. BMW made a number of other enhancements for 2001. BMW sold only 921 in North America in 2001 versus 4,338 the year before.