just to add the RALLIART magna is the fastest non turbo 6 cylinder (quickest car legal under Restrictions)
3.5 L V6
180 KW
0-100 - 6.8 sec
1/4 Mile - 14.7 sec
apparently they could even beat the VT SS and AU XR8.
the VrX Magna also had a 3.5 L V6 which produced 155 KW
so my argument is that the Fastest cars out there for P Platers are sports sedans. EG. Magna, XR6, SS.
Make your choice if you want your car too look cool (imports like, NA supras,skyline, Mr2, 300ZX, impreza etc.all which have reasonable performance) or have the fastest car possible