Jump to content
SAU Community

Recommended Posts

gday guys i need help wiring my rb25 into my r32 gtst im using the rb25 loom and computor and have searched almost evey forum on the internet and cant find much on wiring eveyone seems to be a bit vague on it...

everyone seems to ;leave detailed infomation out so hopefuly from this come some replys and detailed information on wiring can be added to predators tutorial

i folowed the thread by PREDATOR and worked well until the wiring came i did everything correctly that he said

constant 12v to grey wire near afm plug (injector feed)

ign/ to blue with red trace-on plug that went to little brown junction box

earth/ to black with silver blotches-on plug that went to junction box

my r32 wil stil not start..i looked at the ecu and the red light does not come on ..in my understanding this means ecu stil is not getting power

i can crank the car but does not fire

if any one can help me out with some pics of some information of there own conversion that is running wil be muchly appreciated

i just want to get the motor running for the moment wil worry about other things later

cheers travis

Link to comment
https://www.sau.com.au/forums/topic/259802-r32-gtst-rb25-wiring-help/
Share on other sites

hey mate,

check wether you have a full 12v power at your eccs relay, as with mine i found there was a power wire that runs from in the 33 dash that provides the power for this relay (and coil pack relay too if its series one) and is the constant power from the computer.

i'll try an dig out what pin number it is on the computer

you should also connect at least the monitor/ check lamp (cat light on the dash)

but a car would crank if the ecu wasnt even connected . it just means it wouldnt fire as the starter motor has nothing to do wih the ecu..(wel in a 32 anyway)

i just need to find someone who has done this conversion and get the wiring explained a little bit more detailed..as i am not the only person on this forum looking for a good wiring write up

cheers

gday mate thanks for quick reply im not sure how to tel wat series motor i have...

it has two blue relays near th ecu

i think not to sure but think it came from 1994-95 r33..

The R33 Rb25 loom is wired quite differently to the R32 RB20 loom. The main differences include the location of the main power feeds for things like injectors, IGN coil rely, ECCS relay etc. I have prepared a BASIC guide on wiring the main power feeds previously (search my user name) but it is also important to ensure you connect the relevant ECU wires to get it started (eg. fuel pump relay Pin 18, START signal pin 43 etc).

The main power feeds for the RB20 are supplied via the wires connected to the 8 pin plug near the power steering reservoir whereas the RB25 obtains the main power feeds from the plug near the ECU (ie the plug the connects to the body loom in the passenger footwell). Whenever I wire up a loom for someone, I always utilise the original RB20 plugs that mate with the main body loom (ie 3 plugs at passenger footwell and plug near the power steering reservoir) and integrate them into the RB25 loom making it essentially a plug'n'play loom.

You will also need to ensure you remove the water temp sensor for the climate control (on firewall at back of inlet cam cover) and the fuel pump dropping resistor wires (silver rect plug near P/S reservoir - valid if car is originally turbo and you haven't directly earthed the fuel pump) and integrate them into your RB25 loom. I also always use the original wiper plug and wires as the RB25 has a different control of the wiper motor.

If it seems too hard I offer SAU members a plug'n'play loom for $350 + postage. If you supply me both the RB25 and RB20 looms I will produce a plug'n'play loom which literally plugs straight back in and away you go. I wire up everything including tacho, A/C, VCT, boost solenoid, FICD (I add a relay to switch it on when the AC is swithed on), O2 heater, Air regulator etc. Turn around is 1 week or better.

Cheers,

Ben

RB25_into_R32_Wiring_Guide.doc

Edited by BH_SLO32
definately consider ben if you cant seem to get it working for yourself!! best $350 i have EVER spent.. plugged straight in and car started 1st go..

Thanks Daniel, it is good to hear it all went well. I only just finished an RB25 conversion in my sisters car last weekend. Power FC goes in this weekend and she should have a grin from ear to ear!

  • 1 month later...

Can anyone axplain how the power feed works on the RB25 series 2? I finished connecting all the wires to the dash (the 3 R32 plug are now on the RB25 harness). But I still can't figure out how the power goes...On the plug (8 pin) near the power steering I have 7 wires which are:

1. Green/red = signal to A/C

2. Yellow = ????

3. Green/orange = Neutral switch

4. Light blue = Power steering idle up

5. Blue/red = wiper IGN

6. (thick)Red = ????

7. (thick)Red/blue = ????

Hope someone could help.

Edited by BigC1988
  • 3 months later...

A massive thanks goes to BH_SLO32 for providing the basic guide. :(

This guide got the ball rolling for what took less than a day to do, started first go. :P

http://i223.photobucket.com/albums/dd81/30...pg?t=1248868491

http://i223.photobucket.com/albums/dd81/30...pg?t=1248868502

http://i223.photobucket.com/albums/dd81/30...pg?t=1248868506

Edited by Alf

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • That's odd, it works fine here. Try loading it on a different device or browser? It's Jack Phillips JDM, a Skyline wrecker in Victoria. Not the cheapest, but I have found them helpful to find obscure parts in AU. https://jpjdm.com/shop/index.php
    • Yeah. I second all of the above. The only way to see that sort of voltage is if something is generating it as a side effect of being f**ked up. The other thing you could do would be to put a load onto that 30V terminal, something like a brakelamp globe. See if it pulls the voltage away comepletely or if some or all of it stays there while loaded. Will give you something of an idea about how much danger it could cause.
    • I would say, you've got one hell of an underlying issue there. You're saying, coils were fully unplugged, and the fuse to that circuit was unplugged, and you measured 30v? Either something is giving you some WILD EMI, and that's an induced voltage, OR something is managing to backfeed, AND that something has problems. It could be something like the ECU if it takes power from there, and also gets power from another source IF there's an internal issue in the ECU. The way to check would be pull that fuse, unplug the coils, and then probe the ECU pins. However it could be something else doing it. Additionally, if it is something wired in, and that something is pulsing, IE a PWM circuit and it's an inductive load and doesnt have proper flyback protection, that would also do it. A possibility would be if you have something like a PWM fuel pump, it might be giving flyback voltages (dangerous to stuff!). I'd put the circuit back into its "broken" state, confirm the weird voltage is back, and then one by one unplug devices until that voltage disappears. That's a quick way to find an associated device. Otherwise I'd need to look at the wiring diagrams, and then understand any electrical mods done.   But you really should not be seeing the above issue, and really, it's indicating something is failing, and possibly why the fuse blew to begin with.
    • A lot of what you said there are fair observations and part of why I made that list, to make some of these things (like no advantage between the GSeries and GSeries II at PR2.4 in a lot of cases) however I'm not fully convinced by other comments.  One thing to bare in mind is that compressor flow maps are talking about MASS flow, in terms of the compressor side you shouldn't end up running more or less airflow vs another compressor map for the same advertised flow if all external environmental conditions are equivalent if the compressor efficiency is lower as that advertised mass flow takes that into consideration.   Once the intercooler becomes involved the in-plenum air temperature shouldn't be that different, either... the main thing that is likely to affect the end power is the final exhaust manifold pressure - which *WILL* go up when you run out of compressor efficiency when you run off the map earlier on the original G-Series versus G-Series II as you need to keep the gate shut to achieve similar airflow.    Also, how do you figure response based off surge line?  I've seen people claim that as an absolute fact before but am pretty sure I've seen compressors with worse surge lines actually "stand up" faster (and ironically be more likely to surge), I'm not super convinced - it's really a thing we won't easily be able to determine until people start using them.     There are some things on the maps that actually make me wonder if there is a chance that they may respond no worse... if not BETTER?!  which brings me to your next point... Why G2 have lower max rpm?  Really good question and I've been wondering about this too.  The maximum speed *AND* the compressor maps both look like what I'd normally expect if Garrett had extended the exducers out, but they claim the same inducer and exducer size for the whole range.   If you compare the speed lines between any G and G2 version the G2 speed lines support higher flow for the same compressor speed, kinda giving a pretty clear "better at pumping more air for the same speed" impression. Presumably the exducer includes any extended tip design instead of just the backplate, but nonetheless I'd love to see good pics/measurements of the G2 compressors as everything kinda points to something different about the exducer - specifically that it must be further out from the centerline, which means a lower rpm for the same max tip speed and often also results in higher pressure ratio efficiency, narrower maps, and often actually can result in better spool vs a smaller exducer for the same inducer size... no doubt partly due to the above phenomenon of needing less turbine speed to achieve the same airflow when using a smaller trim. Not sure if this is just camera angle or what, but this kinda looks interesting on the G35 990 compressor tips: Very interested to see what happens when people start testing these, and if we start getting more details about what's different.
×
×
  • Create New...