S5 Everything Into S4
07-21-15, 08:24 AM
#1
Rider of the Sky
Thread Starter
S5 Everything Into S4
Well...it's been a long-*** time since I was here. Driving other kinds of cars sucks.
Anyway, back and working on my big project with "crunch time" applied. I'm moving and that lit a fire under my butt to finally get this car done. Now, I've seen plenty of threads about putting an S5 engine into an S4 body, and the general consensus is "don't do it" because of the number of changes and incompatibilities, and the focus of those threads is how to deal with the mismatching.
Well, what I've got going on here is an '86 body and dash with an S5-turbo everything else—engine, engine harness, body harness, dash harness, gauge cluster, turbo MAP, and ECU.
Now, everything seems to be going fairly smoothly, but I'm noticing expectantly that the plugs for the relays in the front are different. I've read plenty of times to "check the FSM", but I can't seem to find useful wiring harness diagram info in it. What page should I be looking for to get the color codes on the wires? I can go buy new relays or splice in connecters from the old S4 harness, whichever would be more cost and time-effective; "time" being more important. I'm working on a lot of things at once, so details like "does the ignition tumbler connect to the S5 harness" I haven't noticed yet; are they any other sorts of difficulties I should expect to run across?
Anyway, back and working on my big project with "crunch time" applied. I'm moving and that lit a fire under my butt to finally get this car done. Now, I've seen plenty of threads about putting an S5 engine into an S4 body, and the general consensus is "don't do it" because of the number of changes and incompatibilities, and the focus of those threads is how to deal with the mismatching.
Well, what I've got going on here is an '86 body and dash with an S5-turbo everything else—engine, engine harness, body harness, dash harness, gauge cluster, turbo MAP, and ECU.
Now, everything seems to be going fairly smoothly, but I'm noticing expectantly that the plugs for the relays in the front are different. I've read plenty of times to "check the FSM", but I can't seem to find useful wiring harness diagram info in it. What page should I be looking for to get the color codes on the wires? I can go buy new relays or splice in connecters from the old S4 harness, whichever would be more cost and time-effective; "time" being more important. I'm working on a lot of things at once, so details like "does the ignition tumbler connect to the S5 harness" I haven't noticed yet; are they any other sorts of difficulties I should expect to run across?
07-22-15, 01:48 PM
#2
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manuals are here, Foxed.ca - Mazda RX-7 Manuals
07-22-15, 09:54 PM
#3
Rider of the Sky
Thread Starter
Bit better condition than my Haynes Manual, thanks. It's been through some rough years.
Well then, I guess I'll figure this one out on my own. Still perplexed why people were distinguishing things like "S5 coils" when they seem to be identified as 86-91 for purchase.
Well then, I guess I'll figure this one out on my own. Still perplexed why people were distinguishing things like "S5 coils" when they seem to be identified as 86-91 for purchase.
07-22-15, 10:45 PM
#4
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yeah i'm not sure why that happens.
a lot of stuff is the same, but you run into weird little differences.
a lot of stuff is the same, but you run into weird little differences.
07-28-15, 02:58 AM
#5
Rider of the Sky
Thread Starter
Minor thing, but still bugs me:
Hooking up the S4 P/S pump, the pressure sensor is expecting a black wire and a green/black wire, but the S5 harness just has the green/black. Anyone know where what I assume is the ground wire is supposed to be or a wiring workaround?
Hooking up the S4 P/S pump, the pressure sensor is expecting a black wire and a green/black wire, but the S5 harness just has the green/black. Anyone know where what I assume is the ground wire is supposed to be or a wiring workaround?
07-28-15, 01:38 PM
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the pressure sensors are different S4 vs S5
the extra wire in the S4 is a 12v power.
the extra wire in the S4 is a 12v power.
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07-28-15, 03:28 PM
#8
Rider of the Sky
Thread Starter
As a side note, I finally found the s5 wiring diagram buried in the FAQ; thank you Wankle. The reason the FSM was confusing me in regards to the wiring is because the vast majority of it is a separate book.
08-03-15, 09:59 AM
#9
Rider of the Sky
Thread Starter
Yep. Nothing plus into anything on the S5 harness. Not the doors, not the pressure switches, not the relays, not what I assume is the cruise control computer, not the rear harness, and I think it's missing the air conditioning wiring entirely.
I guess my best option is to reinstall the s4 front and dash harnesses and solder the FEM01/02 and F31 connectors rather than try and rewire dozens of end-point connectors, since both would involve intensive study of the electrical wiring schematics.
At this point I'd probably even just get ahold of an s4 tps, throw in an s4 turbo ecu, and use an s4 turbo engine harness, but unlike ten years ago, it's not so easy to come by those anymore.
I guess my best option is to reinstall the s4 front and dash harnesses and solder the FEM01/02 and F31 connectors rather than try and rewire dozens of end-point connectors, since both would involve intensive study of the electrical wiring schematics.
At this point I'd probably even just get ahold of an s4 tps, throw in an s4 turbo ecu, and use an s4 turbo engine harness, but unlike ten years ago, it's not so easy to come by those anymore.