I was thinking about my old S14 245/245 setup, weight, and what the Z runs (225/245). This Z is 400 lbs heavier than my old S14 was. Between the 2 cars, the rear suspensions are similar, with multi-link geometry and a nice camber curve. The fronts are the difference. The 240sx's strut suspension has almost zero camber gain at the heights that we run, so every degree of body roll is a degree subtracted from tire-to-road angle. That's why people run such high camber on the front for track S-chassis cars (Patrick L once told me 4* gave even tire temps up front!). The Z has a double wish-bone(ish) front suspension that adds camber pretty aggressively. So with that, the Z wouldn't need to run as much front tire because it'll be making better use of it. But still, if you call 225-on-a-Z equivalent to 245-on-a-S14, that doesn't address the 200 lbs of extra mass at each end on the Z, giving the upper hand to the S14.