a friend of mines have a 86 rx7 chasis and have a 5 series turbo engine we need help wiring the motor can anyone give us an advice how to go to by to do this the easiest way. thanks.

 

A standalone is the easiest way.

Between S4 and S5, Mazda basically changed all the wiring in the car. You can retrofit the S5 harness onto the S4 car with extensive modification, but since you are asking the question I assume you can't do that.

 

what will be the best way to go by

 

i have rewire honda civics before

 

Best way to go? Buy an S4 TII AFM, TB, MAP, ECU, front cover & omp (or blockoff and premix) and use all of the existing S4 NA harnesses. Mixing electronics and wiring between series is a huge waste of time that often results in people giving up or creating numerous problems.

Go to the FAQ at the top of this forum for links on doing turbo swaps.

 

Well, then do what RotaryRocket88 suggested or get a copy of the S4 and S5 FSM (wiring diagrams) and start rewiring.

 

can i rewire the under the dash plugs from s4 to s5 ecu. and use the s5 ecu and engine harness.

 

That's part of what is involved, but it's far more work than you would expect. Download both S4 & S5 wiring diagrams and take a look. Offhand, I'd say there are probably about 50 connections on various harnesses to address.

 

If you've rewired Hondas before, you know that the answers to these questions are found by comparing the wiring diagram between the S4 and S5.

 

I have the same problem, Would I make any lead way by just buying a s5 dash harness? Cuz right now my car turns over and the fuel pump is working but it will not start. What do you think the problem could be.

 

i'd go the other way and wire your s4 harness and ecu to the s5 engine like what 88 is saying. Thats the plan i'm using and i got a superafc to help me out with low boost until i switch over to a stand alone system

 

There is no dash harness. There is a front (F) harness, which connects to half of the car. And then there is an instrument cluster (I) harness, which branches off of the front harness. Swapping an S5 front harness into an S4 car is more trouble than it's worth.

Also, starting problems shouldn't even be related to the front harness; the emissions (EM) harness and ECU would be the areas of concern.