I 2nd the brakes. I would do brakes on ANY 240. Dailydriven, track duty, anything. If you are going to drive it put on some better brakes(Q45, Z32, Z33 brembo, etc.)
I'd also suggest a quality aftermarket water temp gauge... It's a known thing that stock gauges suck.
Handling? a 2way diff, and some subframspacers.
Power? A fuel pump, z32 maf, injectors, safcII, and a boost controller.
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