I would say to go with the 240sx. The KA24 motor is extremely reliable and fuel efficient. The car does not have a lot of power (155hp) but its really fun to drive because of its well balanced RWD chassis. It leans towards oversteer but this is easily corrected with some counter-steer. If the car doesn't make enough power, you could swap an SR20DET(220hp) or CA18DET (175hp) for around $3500 but these would probably be a bit less reliable since they are turbos.
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