I have heard of this being done before. A guy i knew had a jdm s5 t2 swap and was using the american ecu. Im not sure about the wiring harness though. I will get the ecu and harness asap but for now i need a motor so i figured why not and get the turbo swap.

My car is a n/a s5

Any tips or know-hows would be great

 

I just did the JDM TII swap into my 89 NA. It was OK to do, but the engine wiring harness attaches to the drivers side of the car, not the passenger side like an american spec TII. So what you do is basically chop off the end of the american spec engine wiring harness and connect it to the stub that was left on the JDM motor you buy. If you are really smart (not like me), you will get the JDM motor with the engine wiring harness in tact. Then you just have to connect the ends together. If you buy a JDM that has been lopped off right at the motor, you have to add about 18" of wire to each and every wire that connects to the motor. Hope this helps. If you have an S5 car (89-91) don't buy an 86-88 TII motor for it. Use an S5 Motor. Don't try to cross match the S4 (86-88) with the S5 in any way. There are some exceptions to this, but it just easier to say S5Car, S5motor....s4car, s4 motor. If you don't have an ecu yet, go ahead and buy a motor with the ecu and wiring harness still attached. It is worth the money.

 

thankyou

 

Use the non turbo series five harness, named the EM harness by Mazda. Only a couple of wires need to be addressed.

HINT: Go to the free online FSM. Go to the Fuel and Emissions section of both the turbo and non turbo cars. Find the Control Unit pages and compare the wires for the ECU b/t the Turbo and then the non turbo cars. You'll find just a couple of differences. Make the changes required.