the hp in an 01' - 05' US M3 is 333.

the hp in an 01' - 02' US M coupe in 315. (due to exhaust restrictions)

the euro hp versus the US hp conversion is equated differently. the euro m is rated at around 10 hp more than the US cars. equates to a true 5 hp gain for lack of emission requirements in euro version.

hope this makes sense.

cheers!