Extreme bump steer??

Originally Posted by NoHyperbole

That is true; however, in this case, both my 350Z and 370Z were equipped from the factory with the same Bridgestone RE050 tires, just in different sizes.

As I pointed out in an earlier post, the only major difference between the two cars is their caster specifications (about +7.0 for the 350Z, but about +5.0 for the 370Z). More positive caster, among other things, equals more heft in the steering and a feeling of more stability; less positive caster equals less heft and a feeling of quicker turn-in. Driving both cars back-to-back will reveal this immediately.