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R32 Rb20-rb25 Swap Info Please....


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Guest Allen Petersen

Got an 91 R32. I got the series 2 RB25 in the car and my wireing guy is not here and I wanted to cheak on how to just do it myself for a change. Looked for an hr or so and came up with nothing conclusive.

I dont need to know how to take out and put in stuff. Just the wireing for the relays, eng harness ect. Any info that will help me get this job done will be great. I have workshop manuals for both R32 and R33 but im not the wire god so the info you guys would give me will atleast be an assett. Help me out guys!!! :(:)

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In short, you need: r32 pinout diagram and engine loom, r33 pinout, wiring diagram and engine loom, multimeter, stanley knife, masking tape and a pen.

trace and label all the wires running to the under dash plug on the r33 loom, then chop off the plug.

trace and label all the wires running to the under dash plugs on the r32 loom as well as the main power plug in the front corner of the engine bay, then flog these plugs off the loom and transfer them onto the r33 loom.

Once you start labelling you will see the sense in what i'm saying.

Remove the wiper plug and box thingy from the r33 loom and splice the r32 wiper plug into the r33 loom (it's easy when you get it stripped out of the loom and look at it).

Strip the knock sensors out of the r33 body loom and use the r32 one on the rb25. It saves problems with hooking into the r32 fuse box later.

And then you have the assorted odd wires left dangling which generally require switched power like the air con idle up solenoid which can be wired in with a relay to trigger off the AC on wire, and the VCT solenoid which just needs a switched ignition source.

You may need to wire in the r32 dropping resistor for fuel pump speed depending on which version of the r32 loom you have as well as a temp sensor for the climate control.

I can't think of anything else off the top of my head. I'm colour blind so don't know colours either, hence the fun of tracing.

If you haven't done wiring before but can read basic circuit diagrams allow a good day and be patient.

I tried to find a pic of a partially complete s14-s13 loom i did recently to give you an idea of the mess you should expect but i think i deleted it in disgust :(

Good luck

Edit: oops, you also need a soldering iron, solder and electrical tape plus an extra relay and crimp on terminals.

Edited by BHDave
Guest Allen Petersen

that sounds like a damn good idea. I will try that out. My manuals are all Japanese so translating them will be a pain but Im sure I wil figure it out. Your idea of tracing it sounds nice and simple. I also already did the wiper motor today and know exactly what you ment. Same thing I did. Thanks for your pointers

If anyone thinks they can add let me know! Thanks everyone!!!! :(:)

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