ECU for an automatc

[HR31COUPE]

Just reading through this thread and thought it might be of interest to others.

I'm currently doing a project where I'm dropping a RB25DETneo into a HR31 GTS-X coupe. My car was auto to begin with and I don't have the funds for a manual conversion at this stage.

I too was going through the process of trying to find an aftermarket ecu that would work with an auto. So I made a call to Mike at MV Automatics here in S.A. and have now got it sorted.

Depending on what type of gearbox you have he can get a shift controller made up to run the trans so you can use an aftermarket ecu.

He said that the tiptronic 34 boxes cannot be used as this was what cam with my engine package.

So what he is doing for me is as follows: I am using my standard RB20 box which he is fitting a stage 2 shift kit to and supplying the shift controller so I can use my PowerFC.

So I'm not sure if the same can be done for RB25DET auto boxes but it might be worth giving him a call to find out. He is in S.A. but he would send parts interstate as I think I recall there was a group buy on shift kits from him a while ago.

His details are

Mike

MV Automatics

1 Stirling RD Blackwood S.A.

Ph: 83700430

Hope that can be of help to some people

[666DAN]

I'm not sure on the other models, but with the R34's the automatic shift computer is a seperate item on the RB25DE equipped cars...the RB25DET and RB20DE have it integrated into the main ECU.

[nedb]

I've dealt with Mike at MV Automatics already for my Stage 2 shift kit but i was unaware they had a shift controller. Do you know what’s included in the controller and how it works.

Also, what is the cost?

R32's come with a separate ECU for controlling the gearbox but I’m not sure how much of a role plays the Main Engine ECU when it comes to shift control apart from communicating to the Auto ECU the REV's, speed and throttle position.

[HR31COUPE]

The controller itself costs $195, I'm not sure exactly how it functions but he said it is what I need to use an aftermarket ecu with the auto trans.

[nedb]

HR31COUPE - thanx for the info, i'll speak to Mike to see how it all works but this could be great little device for ppl wanting to go ahead with aftermarket computers and keep shift quality with Auto gearboxes.

[Sydneykid]

I've dealt with Mike at MV Automatics already for my Stage 2 shift kit but i was unaware they had a shift controller. Do you know what’s included in the controller and how it works.

Also, what is the cost?

R32's come with a separate ECU for controlling the gearbox but I’m not sure how much of a role plays the Main Engine ECU when it comes to shift control apart from communicating to the Auto ECU the REV's, speed and throttle position.

This has been covered a number of times, a quick summary;

An ECU to run the engine is easy

An ECU to run the auto is easy

Getting the engine ECU to talk to the gearbox ECU is easy

The problem is getting the gearbox ECU to tell the engine ECU when a gearchange is happening. And for the engine ECU to have the complex programming to know what to do while that gearchange is happening. The usual stuff like cut/retard the ignition so the load on the auto is reduced while the gearchange is happening. This enables smooth shift quality and lessons the load on the auto which prolongs its life considerably.

Only the standard auto ECU has this programming:cheers:

[nedb]

So is it possible to remap the ECU and retain the shift logic or it would be lost? If it would be lost I guess the only other option would be some type of a pigyback computer.

I'm trying to figure out my next step n this ECU thing has got me scratchin my head.

Any advice?

[Sydneykid]

So is it possible to remap the ECU and retain the shift logic or it would be lost? If it would be lost I guess the only other option would be some type of a pigyback computer.

I'm trying to figure out my next step n this ECU thing has got me scratchin my head.

Any advice?

In an R32 ECU you can easily tune the fuel and ignition maps. It has no effect on the shift logic.

[32vspecII]

unless you have a r34 or a stagea with the r34 neo rb25 and ecu you cant get daughter boards . there is a guy in the forsale section who has something for sale but only he can tune it and workshops who have tried to get information about it from him have failed . What I think he is doing is taking your ecu and replacing it with another nissan ecu that can be chipped and modifying that for the r33 . There are a couple of places around that do similar things . But I dont know how those other factory ecus will handle the r33 auto , those workshops have only done manuals . in theory it will still work .

No aftermarket ecu will operate the auto the same as the stock ecu , all will have a degree of problems . Even NIB admited after direct questioning .

"Aftermarket ECUs all effect autos but we have had no real problems.

Worst case we have had is like a mild shift kits been fitted."

http://www.skylinesaustralia.com/forums/sh...highlight=arkon

Your only alternative is to use and interceptor type of device such as emanage or safc . However as you are modifying the load data going to the ecu it will also effect the auto transmission to a lesser extent as it uses that load information to change gears .

So thats basically it , R32 or R34 rechip or interceptor , R33 interceptor

or manual conversion

[666DAN]

I've used the e-manage for over 50,000kms now and not had any issues with the gearbox??? The box itself is now 160,000kms old and only show signs of slight slipping due to the power output.

[Chris Wilson]

I have read all the posts (several times) and I haven't seen anything that explains how the Wolf handles the igntion cut/retard on gearchanges.  The standard auto ECU has this feature to make the gearchanges smooth and lessen the torque shock on the transmission.  I have an auto Stagea and would really like to change the ECU but not at the expense of shift quality and gearbox durability.  So can you please enlighten me?

The upcoming new Motec sofware release will handle cut very elegantly, I am told. Also much better traction control and other improvements. Not even in beta here in the UK, but i KNOW it's in testing in alpha.

[32vspecII]

for the price of a motec , you could convert to a manual and a powerfc .

hell for the price of some of the motecs you could get a rb26 and manual

[darkhalf]

i have basic design plans for making an r33/r34 daughterboard on stock ecus. i guess this would help you guys esp if the software was available to anyone to retune

http://home.iprimus.com.au/darkhalf/nistune

badbiki was guaging interest for this a while ago but not much feedback and i have been busy with the tuning software (currently r31/r32 but will retune r33/r34) if enough people are keen i would actually start working on some hardware

[pkblade]

The controller itself costs $195, I'm not sure exactly how it functions but he said it is what I need to use an aftermarket ecu with the auto trans.

HR31COUPE - thanx for the info, i'll speak to Mike to see how it all works but this could be great little device for ppl wanting to go ahead with aftermarket computers and keep shift quality with Auto gearboxes.

I spoke to Mike from MV Automatics today at a motor expo & this 'control unit' HR31COUPE speaks of makes the standard trans behave much like a mechanical trans (eg. tri-matic/ powerglide systems)???. So, basically you have to manually shift the gears, with O/D off as top gear & it would be wise if you invested in a bigger trans cooler & upgraded valve body(shift kit) at this point.

He also, mentioned with the fittment of this control unit the lever select position display lights may not work.

The controller can be fitted on various applications, including the RB25DET. For day to day driving it is still bearably, but its an option more race orientated.

[Adriano]

I believe that most(if not all) aftermarket ecu's would be able to work with the auto computer, if there is an auxillery input, hook it up to the auto computer and set it up so the ignition timing is retarded when the ecuy receives the signal. If there isnt an aux input, you can hook the auto output to a transistor and ground the coolant temp sensor. Seeing a coolant temp of whatever that results in, set that load point to retard the timing, there is a section in the Autronic manual that shows how to do it, i just dont think you could do it with a PFC, maybe with datalogit

[N I B]

V500 Wolf just use one of the inputs and you can make the ECU do anything you want.

[aphid]

i didn't really think there was any "logic" to it as such imo, i thought the tranny control unit sent a +5v signal to the engine control unit, at which stage it would seriously retard/completly cut the ignition..

the tranny control unit handles all the "thinking" or logic i guess in sydneykids terms in gear selection via a map similar to the ignition or injector maps in the ecu, using RPM and engine load (from the tps sensor) to select the correct cell..

i think a better way of getting the power FC to handle the auto transmission would perhaps be to wire the ground from the coil packs +12V supply line through a transistor with the ignition cut wire in a fashion so that when the tranny control unit sent the signal it would drop all ignition, and when it had finished shifting ignition would be restored..

only problem i could forsee with this is perhaps running rich for the instant during the gear shift, however my mates auto r34 seems to give the odd backfire on gear changes anyway.. might be worth looking into?

[benny bobo]

V500 Wolf just use one of the inputs and you can make the ECU do anything you want.

I just emailed Robbie from WolfEMS.

He said that if it is just a voltage signal (i.e. 5VDC) coming from the auto controller to signal shift, into the V500 AUX, it should be able to be configured to R&R...

[T04GTR]

so long as its a r33. you can run anything on it. you just need to suply the seperate auto ecu a tps and rpm signal. easiest way it to look at the wiring diagram of the auto ecu and see which ones go to the engine ecu

[dangerman4]

if its a S1 r33 gtst, you dont need to wire anything just plug the pfc in and away you go.