Quote:
Originally Posted by Great White
Good question ! because actually the rear diff does give a certain extra down flow, at least my Hamann works beautifully since I´ve put it on 
The car was very unstable at highspeeds B4 I had it on & it doesn´t weigh all that much ! |
That seems very unlikely IMHO - that an aftermarket diffuser, likely developed without wind tunnel time, somehow made the M3 significantly more stable.