Jump to content
SAU Community

Information About Rb25 Automatic Transmisson

reebdreworx
 Share

Recommended Posts

reebdreworx Newbie

reebdreworx

Posted
Posted

Hi Forum,

I need to know what information a RB25DE 5-Speed AT Gearbox management ans the ECU are Exchanging. I already look on the wires. Two of them have a sqarewave signal and on the other signal is some noise I don´t understand. The things I guess these both ones are exchanging are ignition cut for gearchange and some diagnosis data. So I´m searching for all information about it I can get. Maybe you guys can help me. That would be awsome.

Now the part why I need this Information. I want to hook up a RB25DE 5-Speed AT to a RB26DETT ECU :-). Because the RB26DETT some much more cool features.

The engine will be a RB25DE that is modified to be a RB25DET including the piston cooling.

Regards Alex

the stink Explorer

the stink

Posted
Posted

I hooked up a datalogger to my 4 speed auto in my R33 and found 4 wires of interest

Pin56 - Throttle position sensor signal to gbox (variable voltage)

Pin5 - Was some sort of decelleration signal that seemed to trigger when decelleration was above a certain level. Signal from gbox to main ecu (goes low on activation)

Pin 14 - Power upshift signal which activated on 1-2 or 2-3 upshifts at high throttle. From gbox to main ECU (goes low on activation)

Pin 15 - Was some sort of acceleration signal that seemed to trigger above a certain throttle position but this varied a little. Main ecu to gbox (goes high on activation)

Might be similar in the 5 speeds but i don't know for sure...

I would be interested to find out more about what is happening in the computers but there doesn't appear to be much info around.

neil

  • 1 year later...
Cold_Fusion Rookie

Cold_Fusion

Posted
Posted

Well I must say i am after similar info (which I also can't seem to find on the net). My R32 5 speed auto is really on its way out. Prob never looked after from the start and I want to fit in a R33 DET 4 speed (3 + O/D for the purists) with the associated gearbox ECU but I wonder if it is straight forward. Are the signals all going one way? i.e. from engine ECU to gearbox ECU.

Essentially I'd like to know if I can get the R32 RB25DE ECU to operate the R33 RB25DET gearbox ECU without hiccups. Thanks for your opinions :laugh:

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • silviaz
      Steps to DIY sanding car back ready for respray....

      By silviaz · Posted

      So I'll put filler past the repair area a bit to make sure I don't miss anything. Then I'll block it until it's almost level, put the guidecoat, then keep blocking until it's gone. Then it's still wavy.  In regards to hitting the panel, I saw this video might give more context - Skip to 0:47 he knocks it down. But yeah I'm sanding until the guidecoat is gone then checking because otherwise my filler is still well above the bodyline. Unless what you're saying is I should put guidecoat around it early, surrounding the filler then stip once it's gone?
    • GabsReDeal
      R32 GTS (RB20DE) Injectors Replacement

      By GabsReDeal · Posted

      I refreshed the OEM injectors with the kit and connected it up. It now ideals okay even with the IACV removed. Driving still has the same cutoff issue like the 550cc injectors so the issue is somewhere else. I bought FPG's Fuel Pump Hanger. I will be installing it next, but it is not as straightforward as I thought it was with my limited wiring knowledge and no instruction on the specific model I purchased (FPG-089). I also got the incorrect billet clamp as I could not find info on the OEM sizing.
    • MBS206
      Leaking Rear Subframe Bushing?

      By MBS206 · Posted

      Stop looking at the garage floor, and turn the radio up a bit louder if there's any strange noises...
    • GTSBoy
      Unknown sound similar to BOV on positive boost with partial throttle RB26

      By GTSBoy · Posted

      No. Turbo shuffle and surge/flutter are not the same thing. Specifically, on a GTR, turbo shuffle has a definite meaning. On a GTR, the twin turbos are assumed to be the same thing and to operate the same way, exactly. In reality, they do not. Their exhaust sides are fed and exhaust a little differently, to each other. Their inlet sides are fed and exhausted a little differently, to each other. Consequently, when they are "working" they are often at slightly different points on the compressor map compared to each other. What this means, particularly when coming on boost, is that one of them will spool up and start producing extra flow compared to the other, which will put back pressure on that other compressor, which will push the operating point on that other compressor up (vertically). This will generally result in it bumping up against the surge line on the map, but even if it doesn't, it upsets the compressor and you get this surging shuffle back and forth between them That is "turbo shuffle" on a GTR. It is related to other flutter effects heard on other turbo systems, but it is a particular feature of the somewhat crappy outlet piping arrangement on RB26s. There are plenty of mods that have been attempted with varying levels of success. People have ground out and/or welded more material into the twin turbo pipe to try to prevent it. Extending the divider inside it works, removing material doesn't. There are aftermarket replacement twin turbo pipes available, and these exist pretty mush purely because of this shuffle problem.
    • Duncan
      Leaking Rear Subframe Bushing?

      By Duncan · Posted

      You can temporarily* use lock collars to keep it in place until you can do the bushes, back the nuts off, slide them in, snug back up. *temporarily is often for ever
×
×
  • Create New...