Also, things to watch out for on S13 that will cause you a lot of headache:
Overheating
Leaky Power Steering
Shot rear subframe bushings
Non-working power windows (if equiped)
Poor idle/no O2 sensor/crappy gas mileage
Noisy/broken timing chain guide (under valve cover at the front of the engine)

Trust me, I've seen underneath many a 240.