alright, 90-91 ls is obd 0. 92-95 is obd 1. 90-93 is considered b18a1. in order to put the 92-93 ls motor in your car you'd need to use a distributor, ecu, injectors off ofa 90-91 obd0 motor. the 92-93 b18a1 motor is 10 horsepower more, and like 5 or so lb. ft of torque more. The parts are interchangeable for pretty much everything