Hey guys, I was wondering if it's possible to convert an s4 harness to an s5 and EXACTLY what would have to be done? forgive me for not searching (I've done a little just not as much as i could have), had an exhausting day and just wanted to post this before I headed to bed so I can start reading in the morning. Thanks in advance for anybody's help!

 

Which harness, and what is going into where?

 

The difference between the S4 and S5 harnesses are everything.

You'll need to pull a wiring diagram of both harnesses (using the FSM) and compare.

What exactly are you trying to do?

 

Well, I have an s4 harness, but s5 motor that is going into my FB. If I absolutely have to I will get the s5 harness, but if it is possible to convert it I'd love to know.

 

I should also probably say its a s4 turbo harness and I have a s5 turbo motor

 

So to sum it up FOR MY 82 RX7:

I have a full S4 T2 harness (will be getting either S4 or S5 ECU, depending on which is easier)

I am FOR SURE getting an s5 T2 Motor, don't try and convince me otherwise (with GSL-SE front cover, and GSL-SE oil pan, racing beat mount, custom spacer for tranny mount, custom driveshaft, T2 tranny yoke)


So basically my question is, what's the easiest way to wire this into my car? I'm not worried about the mounting part, I have that all figured out, just somewhat confused on what to do for the wiring

 

S5 harness is easier by MILES. Don't waste your time with the S4 harness on and S5 engine.

 

sell the s4 harness and get an s5 Harness..Done!

 

If you are planning on upgrading the turbo, why not start with a full standalone?

 

That's not an option at this point. I'm getting the stock motor running, then I'll worry about upgrades in the future.

 

Yeah I figured the S4 harness would cause some
Issues. My buddy is stopping by soon here with another harness, crossing my fingers that its an S5

 

So this can be closed. Buddy of mine has a complete S5 TII setup w/ AEM standalone and a few other goodies for a price Id be dumb to turn down. Thanks for all the attempted help guys

 

yeah it would be a total waste to put a FC harness in a FB to run a 13BT. cheap used stand alone or even a mega squirt. stock ECU is why modified turbo cars are not on the road.

 

Haha it would have been fine with the stock ecu to get it running. Never said I was gonna modify it with the stock ecu