Help With Rb25 Into R32 Wiring

[nick81xd]

currently putting a series 1 rb25 into a r32,

Swapped over the engine loom to a standard rb25 computer and wiring harness and currently trying to sort out the wiring for the 2nd loom (starter, alt, oil pressure, gearbox wiring etc.)

Does anybody know what exactly needs to be done to get the 25 loom to work with the r32 fusebox and exsiting wiring.

Auto electrician did not know what to do even with supplied diagrams.......

Have searched and there is no clear guide on what to do exactly.

Any body have answers?

Thanks

Edited May 15, 2008 by nick81xd

[blind_elk]

What excactly are you having trouble with? The alternator, etc wires simply plug exactly as the did to the RB20 - at least they did when I did the same conversion, and I installed a full custom loom aftermarket ECU.

[nick81xd]

the guy wants to use all the standard computer and wiring, most of the 25 wiring all plugs in except for a white 6 pin plug that goes to the motor, but the main problem is where the the 20 loom goes into the fuse box, the plugs are completely different.

i would use the 20 loom except the loom doesnt have knock sensor wires and the white 6 pin plug to go to the motor.

90% of the conversion is done just need the wiring to be sorted to finally finish it.

[nizmonut]

i shoved one of these 25's in a hilux.

on the loom find a 16 gauge grey wire. this is 12 volt injector feed

8 gauage white wire coil 12 volt feed

....................the above two should be spliced togther directly to a relay near the ecu kickpanel.

pin 16 16 gauge orange wire ecu power feed 12 volt (to eccs relay)

pin 18 16 gauge black wire pink stripe. fuel pump 12 volt feed.

pin7 ecu 16 gauge yellow with blue stripe tacho signal

pin 43 16 gauge grey wire red strip signal wire to ecu from ignition switch

direct to dash 16 gauge blue wire temp sensor

these should get your engine running

http://www.meggala.com/rb25detenglish.html

Rb20det_pinout.txt

[PRO_32]

What excactly are you having trouble with? The alternator, etc wires simply plug exactly as the did to the RB20 - at least they did when I did the same conversion, and I installed a full custom loom aftermarket ECU.

Im also in the middle of this conversion.

Did you plug the the starter and altenator into the rb25 loom or the existing rb20 loom thats not part of the rb20 engine loom that stayed in the engine bay after removing the rb20 ( it goes to the relay box)

Also where i unplugged the loom in the cabin kickpanel there is a hell of a lot more plugs than what there is oin the rb25 loom to replace it.??

[BHDave]

i used the rb20 section of loom and stripped the knock sensors out of the rb25 one and ran them separately.

I think i had to enlarge the eyelet for the alternator, but otherwise it fit up. I also installed the rb20 oil pressure sender.

edit, didn't see your second question;

The r33 uses one big dash plug, the r32 has a couple of smaller ones. Probably finding the tutorial by predator will give you a good handle on that side of the conversion but there is a fair bit of tracing, marking and soldering required.

Edited July 3, 2008 by BHDave

[PRO_32]

i used the rb20 section of loom and stripped the knock sensors out of the rb25 one and ran them separately.

I think i had to enlarge the eyelet for the alternator, but otherwise it fit up. I also installed the rb20 oil pressure sender.

edit, didn't see your second question;

The r33 uses one big dash plug, the r32 has a couple of smaller ones. Probably finding the tutorial by predator will give you a good handle on that side of the conversion but there is a fair bit of tracing, marking and soldering required.

BHDave thank you for the speedy reply.

I have gone through Predator's tutorial, (amongst others) and all credit to him as it's mega informative. And the most comprehensive i have come across. not jus on SAU but all over internet land.lol

1. When you say Ran them seperately (knock sensors) do you mean you traced where the original rb20 knock sensors run to and then Ran the RB25 sensors to that same point, Be it relay box, Kick panel inside cab, or be it anywhere else.

2. Speaking of The oil pressure sender On the RB20 It screw's straight into the block. However on the RB25 it screw's into the cast Fatcory oil cooler. I dont wanna run the factory oil cooler and filter As I have a remote filter and cooler setup. And wanna simplyfy and remove that cooler and all associated plumbing any experiance on it, OR idea's.

3.Predator's tutorial whilst comprehensive unfortunatly didnt delve to deeply into the wiring side of things. OR maybe it's jus that im totally hopeless with wiring and i need spelled out to me as clear as day.

Cheers

Andrew...

[BHDave]

1) the knock sensors on the rb25 are part of the (i suppose you'd call it) body loom. They still plug into the engine loom at one of the plugs at the front of the plenum though. So i just cut all the tape off the rb25 body loom and found that the knock sensor wiring could just be removed from the rest of the loom (no cutting or anything) and plugged in. Easy.

2) I kept the factory cooler. Originally i didn't have a separate cooler but now i do. I actually like the factory cooler as it also helps to bring the oil temp up from cold as the water temp rises quicker than the oil temp. oil temp also tends to get higher than water temp even with a dedicated cooler so it still helps.

3) The wiring is a difficult one to explain. I don't work in colours as i'm colour blind which doesn't help a lot of people. I traced each wire into the rb20 dash plugs and referenced the rb20 pinout diagram, then did the same for the rb25 dash plug. Joined up the obvious matching wires, ran some new ones for power (as the rb25 gets all it's power feeds from under the dash but the 20 gets it from the engine bay), stripped the wiper loom out of the 20 loom and used that, can't remember what else, it's been too long....

[BH_SLO32]

I have done a few looms for SAU members now and the most common is the RB25 into R32. I have been preparing a ROUGH guide on the wiring basics for this conversion and provide it to people when they ask. I have been developing it for sometime and it isn't complete but I think it will help. Please note that I have not addressed ALL the wiring connections required to get complete functionality of the RB25 and you will still need to connect the relevant fuel pump trigger wire and start but this should not be too difficult.

Hope this helps.

Cheers

RB25_into_R32_Wiring_Guide.doc

[PRO_32]

Thanks guys mucho helpo..

however Looking at the photo of the 25 loom seems like it has more plugs than mine. Off memory i havent looked at it for a couple of days now and it's too cold to go to hte garage now.

Could this mean that i couuld possiby have a seried 2 rb25??

Thanks again for your help I jus printed out your guide and will look over it 2morrow guessing (after jus a quick scan) a bit of it might not aply to me as it's track car and things like a/c and such do not apply..

Cheers

Andrew...

[PRO_32]

ok it's an series 2 rb25 i got.

1. I dont know how much of your guide applies to me now.? gotta do more investigation.. Any thoughts.

2. Removed side loom off rb25 seems like it only services starter, gearbox sensors, altenator and 2 other plugs (which i dont know their intended use) does not look like it will affect me anyway.

3. Removed altenator also. Gonna use rb20 altenator as using rb20 side loom.

4. Factory oil cooler/ coolent heater. removed. Unlike the rb20 oil pressure sender, the rb25 one is located in the cast cooler fitting. however looks like there is a tapped thread that can be used just above the factory unit. ( will post picks 2morrow after work.

5. Will probably use rb20 knock sensors havent stripped back enough of the loom yet to decide (But thats what predator said to do.)

6. hicas now completely removed was gonna run cooler for P/S of rear pump. (as per S/K instructions) but have now decided to ditch rear pump and run a cooler inline from P/S rack return to res. Reason for that is to simplify the whole thing also thats where the heat will be generated so cooling it upon return to resevoir seems to make sense.

7. Removed ABS ( i know alot of ppl are against this) unit completely jus gotta get some non abs brake lines for the engine bay now. Doint know if i gotta change booster or not will figure out eventually i spose.

8. pizza has arrived so will pick it up l8r..

[BH_SLO32]

ok it's an series 2 rb25 i got.

1. I dont know how much of your guide applies to me now.? gotta do more investigation.. Any thoughts.

2. Removed side loom off rb25 seems like it only services starter, gearbox sensors, altenator and 2 other plugs (which i dont know their intended use) does not look like it will affect me anyway.

3. Removed altenator also. Gonna use rb20 altenator as using rb20 side loom.

4. Factory oil cooler/ coolent heater. removed. Unlike the rb20 oil pressure sender, the rb25 one is located in the cast cooler fitting. however looks like there is a tapped thread that can be used just above the factory unit. ( will post picks 2morrow after work.

5. Will probably use rb20 knock sensors havent stripped back enough of the loom yet to decide (But thats what predator said to do.)

6. hicas now completely removed was gonna run cooler for P/S of rear pump. (as per S/K instructions) but have now decided to ditch rear pump and run a cooler inline from P/S rack return to res. Reason for that is to simplify the whole thing also thats where the heat will be generated so cooling it upon return to resevoir seems to make sense.

7. Removed ABS ( i know alot of ppl are against this) unit completely jus gotta get some non abs brake lines for the engine bay now. Doint know if i gotta change booster or not will figure out eventually i spose.

8. pizza has arrived so will pick it up l8r..

Fear not as the only significant change to the wiring for a series 2 RB25 is the power feed for the injectors and there is no ignition coil relay near the ECU. The injector feed on the series 1 motors is a dedicated feed coming from the 8 pin plug near the P/S reservoir whilst the series 2 loom has a common feed for the coils and the injectors.

I would recommend not touching the factory R32 body loom down the drivers side (starter, alternator, oil pressure etc). What I do recommend to people planning to do this conversion is to grab the R33 body loom wiring on the drivers side when purchasing the RB25 as it incorporates part of the engine wiring loom. I normally get people to send me this loom so I can remove the knock sensor wiring and the air regulator wiring. This wiring terminates in one of the 2 grey plugs in front of the intake manifold (see photo). I have also attached another photo of this wiring after it has been removed from the body loom wiring and wrapped as a separate mini loom.

Dont forgot that in addition to the major wiring modifications I have mentioned in my guide, you still need to connect all the other ECU wires like start signal (pin 43), tacho (pin 7), fuel pump relay (pin 18) etc.

Cheers

Edited July 5, 2008 by BH_SLO32

[PRO_32]

Fear not as the only significant change to the wiring for a series 2 RB25 is the power feed for the injectors and there is no ignition coil relay near the ECU. The injector feed on the series 1 motors is a dedicated feed coming from the 8 pin plug near the P/S reservoir whilst the series 2 loom has a common feed for the coils and the injectors.

I would recommend not touching the factory R32 body loom down the drivers side (starter, alternator, oil pressure etc). What I do recommend to people planning to do this conversion is to grab the R33 body loom wiring on the drivers side when purchasing the RB25 as it incorporates part of the engine wiring loom. I normally get people to send me this loom so I can remove the knock sensor wiring and the air regulator wiring. This wiring terminates in one of the 2 grey plugs in front of the intake manifold (see photo). I have also attached another photo of this wiring after it has been removed from the body loom wiring and wrapped as a separate mini loom.

Dont forgot that in addition to the major wiring modifications I have mentioned in my guide, you still need to connect all the other ECU wires like start signal (pin 43), tacho (pin 7), fuel pump relay (pin 18) etc.

Cheers

Ah yes i see what you mean i have stripped all but knock sensors and air reg wiring away from rb25 side loom. pretty much looks like your pic now.

when you say"you still need to connect all the other ECU wires like start signal (pin 43), tacho (pin 7), fuel pump relay (pin 18) etc."

Do you mean from ecu to in cabin loom??? not sure i understand what you mean?

Sorry for the Noobness, Very much a greenhorn with wiring, However determined to do it all myself as with nearly everything with my car. so your help is greatly appreciated.

Cheers

Andrew.

[BH_SLO32]

Ah yes i see what you mean i have stripped all but knock sensors and air reg wiring away from rb25 side loom. pretty much looks like your pic now.

when you say"you still need to connect all the other ECU wires like start signal (pin 43), tacho (pin 7), fuel pump relay (pin 18) etc."

Do you mean from ecu to in cabin loom??? not sure i understand what you mean?

Sorry for the Noobness, Very much a greenhorn with wiring, However determined to do it all myself as with nearly everything with my car. so your help is greatly appreciated.

Cheers

Andrew.

Yes, the R32 has 3 cabin plugs whilst the R33 has either 1 (or sometimes 2) long rectangular white plugs. I always remove the R32 plugs and then connect each plug wire to the corresponding RB25 wire. To do this you will need to spend sometime identifying all the wires in both the R32 and R33 cabin plugs and then join the wires where required. You can identify the wires through the aid of the pinout diagram and wiring diagram for the R32 and R33 motors.

I have attached a photo of a loom I did sometime ago which shows one of the R32 in-cabin plugs with wires soldered to the appropriate wires in the RB25 loom. You can also see the original RB25 white plug.

Hope this helps

Cheers

[DC Drift]

Dont forgot that in addition to the major wiring modifications I have mentioned in my guide, you still need to connect all the other ECU wires like start signal (pin 43), tacho (pin 7), fuel pump relay (pin 18) etc.

i dont know what pin is 1 lol

what colours are they im lost?? lol

[DC Drift]

Fear not as the only significant change to the wiring for a series 2 RB25 is the power feed for the injectors and there is no ignition coil relay near the ECU. The injector feed on the series 1 motors is a dedicated feed coming from the 8 pin plug near the P/S reservoir whilst the series 2 loom has a common feed for the coils and the injectors.

what wire is this guys??