cheapest motor is probably the 1st gen b16a or the ZC

best power to price ratio is the h22 but you will need know-how to do that and its not easy. it can get expensive if you have problems or arent good with your hands and imagination.

the b16a2 and b18c1 are the 2 most expensive options here, but everything bolts up for the most part.

i also recommend you get an OBD1 motor.

~boom