Single overhead cam, and double overhead cam. Double overhead cam motors have more power, and I am pretty sure 4 valves per cylinder. My wife's 98 Neon had SOHC motor, ran pretty good(until a drunk totalled it). The engine should have the type writtten on it, can have the vin number checked to be sure. Do not know much about fixing them up but Ebay is s good source for body mods. Seems to be a lot out there for them.