hi adc.
Ofcourse the discussion between the 135i and m3v8 has to be between stock cars, not a havily modified 135i against a stock M3v8. But still a havily modified 135i(!) cannot keep up with the M3v8. Here is one test between the M3V8, Schnitzer ACS1.35i (360bhp) and the Evotech 135i (400+bhp). There are more tests, have to look up.
http://img138.imagevenue.com/img.php..._122_949lo.jpg
http://img164.imagevenue.com/img.php...jpg&loc=loc817
360 135i against M3v8