I've got a chance to pick up a non turbo '91 RX7 with a good motor, but will the motor work in my non turbo '87 RX7? It is a 13B motor and looks a lot like the one in the '87 but I'm concerned about the wiring harness from the ECU and of course all the other extranious stuff that has to hook up to it to include the manual transmission. Can I take the entire wiring harness from the ECU, and the ECU, out of the '91 and put it all in the '87?

 

Yup.

 

Yup to which question? All? Do I need to swap the ECU and harness or will the original work?

 

I believe you'll need the ecu and harness....search around I know there have been countless discussions on this.