How can you tell the difference between a turbo and nonturbo on a 1988 supra?

Look on the front timing cover. If it says 7MGE it is non turbo, if it says 7MGTE it is a turbo. You can look on back below taillights for turbo emblem. The turbo motors also usually have a black plastic cover over the front of the motor that says turbo. Easy way is look on left side of motor where the exhaust is to see if there's a turbo or not.