Will I get bennefits from changing the stock ECU of my 81 N/A, to the ECU of a turbo 280zx? If yes, will it be a plug on, or will I have to modify something?

 

You will get no advantage. You will loose gas mileage because your car will run very rich at high rpm's.

These computers are very simplistic (ie. 1975 technology) and are not flexible. You do something to the motor that the ECU doesn't understand and it will ignore whatever you've done and keep treating it like you didn't do anything making the car run like crapola. (<Technical term from the '80s)

 

Not to mention that fact that the ECU plugs are completely different... You'd have to swap the entire wiring harness, and w/ out all the turbo sensors hooked up right, won't work right anyway.

Nice try tho!