I think that one the track, the m3 would win hands down - it has better braking and acceleartion times. It was made and developed for the track, not for street driving. The mclaren was a track car and adopted to the streets. Now in a street race, the mclaren would probably win - the m3 can only get up to around 160mph (i think) due to gearing and that it doesnt need to go any faster for the track whereas the mclaren can go to 230+mph

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