TCU

[qball]

Does this change tiptrnic mode or just when in D?

 

[TME_Steve]

Shift speeds and pressures affect both.

 

[wendnarb]

its the same for tiptronic too.. like you can change the minimum that you can shift at, but if you change how fast the shifts are in drive they will be just as fast in tiptronic!

 

[qball]

Never drive in D so was wondering if i should be interested in this

 

[Hotwire]

All i can add is:

Well done to Bill on determining these defs - transforms the car

I will say, the speed doesnt quite correlate, seems to be about 6-8kph out, i.e. 5th was set to not shift until 50kph stock, and I upped this to 70kph. However actualy minimum shift point seemed to be about 58kph, and is now 78kph (a little high) so I will compensate, but something to watch out for for other players.
I have only modified up shift pressures, and will continue to play with downshift now, but 1.3x seems like a good firm shift without being commodore spec chirpies.

 

[BCX]

I will say, the speed doesnt quite correlate, seems to be about 6-8kph out, i.e. 5th was set to not shift until 50kph stock, and I upped this to 70kph. However actualy minimum shift point seemed to be about 58kph, and is now 78kph (a little high) so I will compensate, but something to watch out for for other players.
I have only modified up shift pressures, and will continue to play with downshift now, but 1.3x seems like a good firm shift without being commodore spec chirpies.

I reckon there is more to it that just that. Also there are some extra tables when i was looking, i have no idea what they are for - i only defined what WytWun had defined. i might define them as 'unknowns' and leave it to you guys to determine.

Will update the XML when i get a chance.

 

[Hotwire]

Sounds good Bill. Happy to work on the TCU definitions, and leave the ECU stuff to you and Steve.
As for meeting up one day to go through some of your untested stuff, i'm free most saturday/sundays after March 10 so let me know if you want to meet up.

 

[gorgath]

Question guys and I do apologise if I am pointing blank here.

Can the auto box tolerate the sudden load after modifying the TCU to be more firm shifting and adjusting speed shifting? As we all know the auto tranny is sensitive and wave springs will not last specially if the car has been tuned as well.

Do you suggest to get the tranny rebuild to be more strong and tough?

 

[TME_Steve]

How long is a piece of string.... depends what youre doing, if youre just making it respond like it does at full throttle at lighter loads i don't see that would be an issue.

Changing shift points is also not going to hurt....

 

[Hotwire]

I called in to speak to Steve knight about this last night. He was able to tell me when they used the W5A51 for the ralliart magna, they upped the line pressures slightly from what Japan gave them. However they were told not to over extend. Also in the later W5A51s they put 3 and then 5 clutches in them, as opposed to less in the early boxes? But the most important piece of info was, if you havent done the low/reverse wave spring and had the carrier pins tig welded, DONT MESS WITH THE LINE PRESSURE.

so yeah, for a lot of people, probably not best idea to up the line pressures (however as i've had these done i'm a happy camper, just depends how quick i wear the clutch i suppose)

 

[TME_Steve]

Just don't go beyone what they already go to, I would say.

 

[merlin]

The shift speed discrepincy actual to the table values is because the table is working in shaft speed, not kph.

Try changing the SpeedAT scaling to toexpr="x*30/25.7" and frexpr="x*25.7/30" and see what you get.

 

[BCX]

New defs with some unknown maps defined. the H -> L and L -> H assumption is based on where on the code and where the other known tables are. I could be way off, but i'd assume any high to low gear table would be in the same bit of code, etc

link for new defs - v1.2

 

[xtech]

so if i swapped my tranny an my TCU will not work with it....... can this TCU simply be re-flashed with a ROM from a compatible TCU an I be on my way again

 

[Precedence]

so if i swapped my tranny an my TCU will not work with it....... can this TCU simply be re-flashed with a ROM from a compatible TCU an I be on my way again

I am having this exact issue right now as well.
When replacing TCU in the car, getting a code 61.

 

[professor_jonny]

Hi I'm wondering if someone would have a copy of the auto transmission roms and definition files mentioned in this thread as the drop box link is dead?

I have a 1998 rvr and I'm trying to create definitions for the transmission it would be handy to have something to study and compare structures etc in the rom.

Also is there a feature to drop revs on the engine (lift to switch) with any current auto roms to reduce the load/ wear on the planetary clutch packs when changing gears?

I'm Planning to upgrade my power output significantly and I just want to make it last as best as I can.

 

[BCX]

TCU defs now included in the broad definitions here

Official OzVR4 Definition & Disassembly Thread

Hey Guys, I thought I’d start this thread as a bit of a brain dump of what I’ve been working on for the last few years with a big help from Steve - TME_Steve & Kenneth. Basically, I got sick of seeing the same crap VR4 EcuFlash definitions, so I’ve gone to the effort of disassembling the VR4...

www.ozvr4.com

As for mods for the TCU, not sure as I never disassembled the rom. Also, I never had access to an auto.

Will look and upload the copy i have of the tcu ROM

Ps. Been meaning to reply to your email!

 

[professor_jonny]

TCU defs now included in the broad definitions here

Cool thanks for the updated links, I have been looking for a TCU rom and definition for a vehicle with a simular chipset this will aid me in maybe maping something on my rom dump and creating xml's.

I actually just changed the xmlid in the vr4 definitions to that of my rom and most of it seems correct to be honest there are obvious differences and errors but it is a massive start.

There is nothing around it seems reguarding transmission ecu modification (apart from the evo X SST done a few weeks ago by hamish ahern and two other guys) wytwun and you are the only people to actually create defs for a transmission rom, and this is the only forum I have even found mention of it and download links.

I do know the transmission processor inside the cars with seperate transmission / engine processors would likely need an input and an output to handshake for a lift to switch function as they only share a few I/o like the tps and are basically seperate entinties inside the same box.

my car is based on a w4a51 transmission and basically everything else is 5 speed so ecu swaps are out of the question but i have found a russian airtrek forum where someone has extensivly modified the airtrek ecu rom and used in on a 4speed auto and I believe even added mosfets to the pcb to run a v6 engine.

As I have been stuck in isolation with the family with covid I have created basic xml's for my rvr now but they are by no means complete or perfect but a dam sight better!!! and are now to the point where I can scale my injectors and maf in the conversion to evo bolt on upgrades.

 

[BCX]

I have a mate that's into Magnas, from memory difference between the 4spd and 5spd roms was table values.
ie you can use a 5spd rom on a 4spd provided the tables for shift patterns had data that would render the 5th inaccessible.

Have a look at Evo 7 GTA defs for more automatic table definitions, then you've gotta find the table in the H8 TCU rom as the EVO7 GTA was superH (in superH world, one processor controlled both ecu/tcu unlike the H8 based ECUs which had either a separate control unit or separate processor on same board like you described.

 

[professor_jonny]

I have a mate that's into Magnas, from memory difference between the 4spd and 5spd roms was table values.

Have a look at Evo 7 GTA defs for more automatic table definitions, then you've gotta find the table in the H8 TCU rom as the EVO7 GTA was superH

I have compared differences by looking at tables in a evo5 for the engine, but my methods are a stab in the park style, with search and compare or look at increasing hex values using winols then tweak maps till it looks like what is should be as the sample in the evo rom as I know no better method.
I don't know if there is some sort of sequence at the start or end of tables it suggests this here and there.

I have been using the wayback machine for info on disasembly but many links are not archived :-(

I loaded my tcu dump straight into your vr4 at base and it seems quite well defined as is as the roms differ very little from the vector table to the end of the last table defined in your xml.

I did notice 2>1 or 1>2 I think it was was all nil values and 4>5 had weird values. which indicates that the likely just fudged a 5speed rom into a 4 speed and possibly tables may be out of order or just not a good fit for my rom or something?

The code segment in the vr4 tcu dump seems to be a lot larger than mine they only produced the RVR x3 in 1997 and 1998 and the rom for the vr4 is likely more mature, that would also be my experience in driving the car as at times you can hear/ feel the driveline really get hammered on some shifts.

They built 200 RVR x3 cars required for homologation rules, they built them with what ever they had on hand to hit that target and there were some truly weird setups.