I believe the 300zx (90+) has a tighter steering rack but I'm not sure what all can be swaped into our car. You could always just get new gears custom made *shrugs* would probably be more money than its worth though...not to mention hard to find someone willing to do it.
You could get an aftermarket wheel. Though the turn radius would still be the same, you'd have to move your arms less since you'd have a smaller wheel.
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