I have an 83' ECU in my 81', just pops in and works great. From what I hear, you can use the 82-83 ECU's in the 81, but you can't use the 81' ECU in the 82-83's. Has to do with the dropping resistors for the injectors. So if you can't find an 81' ECU, look for the 82-83's. Also, the non turbo ECU's won't even plug into the turbo harness, connectors are *totally* different.