For instant passing power and raw accelleration you really cant beat a 70 Olds 442 W-30 with 30 over pistons and a few other tricks. Its fun watching the gas gauge needle sweep down as fast as the speedometer needle climbs.

But that aside, Porsches to me are more fun at over a 130 than under. Its in the upper speed ranges where they really shine. The directional stability, braking, aerodynamics and speed feel are incredible and unique. Its a sensation they should patent and its where they put a lot of their money and engineering.