For example, the motors in the karts Honda put us in spun to about 5,000 rpm to exploit the best of the torque curve, but they can go as high as 9,000 rpm. Just like a conventional kart ...

Stephen Huntley’s instructions to the helmeted drivers standing alongside the autocross track at Lime Rock Park in Lakeville were precise and delivered in a firm tone. “If there’s any contact — light ...