Heh nice A/F line. I'm sure that M3 was stock and here is why.

333 hp @ 7900 rpm
262 ft-lbs @ 4900 rpm

While SIpimpin is making

298WHP@8000rpms
201TQ@6800 rpms

Assuming the M3 is making 280-285WHP and 240-225TQ and both cars with no xtra weight in them I can see the civic pulling 1 1/2 cars on the M3.

Edit: What psi are you running??