TOD controller - knob, wheel, or buttons?

[Knigh7s]

Hey Mbeach,

Just wondering how this project is coming along? I could really use one with my manual hubs from Spazz.

Peer Pressure, Peer Pressure, Peer Pressure

Just kidding. Hehe

[Knigh7s]

^ Wut he said ^ ooh wait that was me?

[taylorRichie]

Thread Resurrection

Wondering if anyone has any further details on this project. I was thinking of developing exactly what mbeach was working on. I've pm'd him hoping to get some response that could save valuable development time.

Just reading this thread and knowing he has had success is enough to make me start the development whether I'm able to get info from him or not.

Does anyone have Pin Out, or TOD wiring, or detailed information? Or know of where resources that give that information?

Seems like this would be the one mod we would ALL like to have. Especially those of us who have winter. Being able to give a true 50/50 split would be nice. Or to shut off the front wheels during our daily drives.

If anyone has any info please point me in that direction.

[Solitude]

I am thinking about going the manual front hubs direction as far as the isolating the front end out of the equation.. I liked the replies I received from this thread

http://www.vehicross.info/forums/showthread.php?t=13588

congrats on finding a powervault 2

I am GREEN with envy..

awesome work on your ride thanks for the log.

Jeff

[VehiGAZ]

I remember this project well - mbeach is an electroinics tech of some sort, so he was definitely the man for the job. He rigged an oscilliscope into one of his VXs (he had two, IIRC) to see what the inputs and outputs of the ToD controller were doing in various circumstances. He tried to get it to happen, but I believe he gave up on it when he realized that the speed-variable square wave generator needed to trick the ToD was too complicated to make as a simple workshop project, and he didn't want to get involved with making them. This was a shocker for some people, because the JDM VX and the Trooper ToD (which offered a 2W-Hi option in addition to ToD and 4WD-Low) could easily be modded to force a 4WD-Hi mode. That mod, however, does not work on the VX. Similarly, since our front hubs do not unlock, we don't want a 2WD-High option, because the front wheels will still end up spinning their drive hardware all the time even if you decoupled the front axle at the t-cases.

Mbeach sold one of the VX's, and he hasn't been around here much since then - his last visit was 2.5 months ago. Anyway, if you REALLY know your electronics, he's the guy to talk to about this (if you can get in touch with him).

Good luck!!

[taylorRichie]

Hey Vehigaz thanks for the response...

I actually found the thread where Mbeach explained where he left off...

The difference between his approach and the approach I'll be taking is... he was just going to add home brew components to the TOD unit in order to accomplish what we all want... Variable TOD...

I will be working with my Brother (electrical Engineer) and he would build custom software to emulate whatever we need.

I'm quite confident we can make this happen, it's mostly a matter of getting the time to do the initial experimentation, and diagnosis. I'm also sure that the knowledge in MBEACH's head would prove invaluable to resurrecting this project.

We'll see how it goes...

----

Thanks Jeff!
That's a great thread, I've read over it a few times... I think the best combination would be a TOD controller, and manual hubs

Richie

[taylorRichie]

Where the project left off

This one has been beat to death, and sadly, I never got to finish my work on it before I sold 0723. Now the test mule (complete with my custom made TOD eavesdrop harness) is laying dead behind a BMW dealership in Anchorage...

The E-clutch that engages the TOD is activated by a modulated voltage -NOT direct current. While DC will lock up the clutch, engaging the front driveshaft, it will also burn out the e-clutch over time.
You might be able to search my gallery for photos of the TOD computer in operation (look for the o-scope pics).

In order to have reliable 4hi, you need to generate the 88% (iirc) PWM signal that simulates the TOD computer's signal, and send that to the blue wire.
Google "DC Speed Controller" to get an idea of how PWM is used to control inductive devices like motors and clutches.

A few of us got a long way into figuring this out, and we pretty much had the solution on paper. Picture a knob, that allowed you to dial in the exact amount of torque you wanted to go to the front axles. Pretty cool.
However, no one really managed the jump from paper to reality for whatever reason.
Mine was a lethal combination of laziness and wife.

There are also two huge reasons that this knob solution never took a priority:
1. The Ball Ramp Mechanism. The original purpose of the TOD controller was 2hi, not just 4 hi. Two-wheel-drive has all kinds of practical daily benefits, not just the occasional mud run. Unfortunately, even with the blue wire disconnected (toggled), there is a mechanism within the Borg-Warner T-case that still transfers rotation to the front driveshaft. The e-clutch simply modulates this rotation to create torque. Tone discovered this phenomenon on a 2wd dyno, with disasterous results. So, unless your front wheels are suspended in the air (no friction at all), 2hi is unobtainable.
2. TOD is awesome. There was an army of engineers behind this one, and us lowly mortals could never improve its function. The truth is, that with a mechanical T-case, there is no way to reliably control it's doings from the driver's seat. The DCCD in the Subaru STI is on a viscous center diff, like the Evo -this is not a mechanical transfer case. I know that the Baja VXs have a torque controller (at least you can see the knob from the pics), but they also have a warehouse full of spare parts...

So, Tad's solution on PI is great, but use it with care (just like the owners of Air Lockers do). If you leave it on for an extended period, you will break something -it's about the size of a hockey puck and it's buried deep within your transfer case.

Not finishing the TOD speed controller has been one of the greatest automotive letdowns of my life. I really wanted to finish this one up, if only to say it was done.
I still have all of the files though...

[taylorRichie]

I PM'd MBEACH asking for any details on his project... I think he provided me with invaluable information. I've passed the details on to my brother (the engineer) and I'm anxiously awaiting his response.

This project seems like it'll be cake for him (since Mbeach did basically everything but the final build)

Thanks again for the response MBEACH!!!!

Richie

[Ldub]

I PM'd MBEACH asking for any details on his project... I think he provided me with invaluable information. I've passed the details on to my brother (the engineer) and I'm anxiously awaiting his response.

This project seems like it'll be cake for him (since Mbeach did basically everything but the final build)

Thanks again for the response MBEACH!!!!

Richie

Put me towards the top of the list if this comes to fruition...

Then get the Bro to work on a program so that we can tweak the ECU for greater mileage, performance & the ability to tune to the fuel/air sweet spot in supercharged applications....

[blacksambo]

Hear, Hear... great! Nice that somebody is able to work on this project. You know, you can turn off the TOD on the Trooper but not the VX.

[Knigh7s]

This is good news!!! I was pretty bummed when the original project halted...

So now that we are on topic of TOD and stuff. Anyone know exactly what JDM TOD unit/parts would be needed to do a conversion?

[taylorRichie]

can't help on the jdm conversion but can give an update... We've started some prelimary design... By we I mean my brother...



It will have a small LCD screen and two buttons for changing your tod front percentage

[PK]

This is good news!!! I was pretty bummed when the original project halted...

So now that we are on topic of TOD and stuff. Anyone know exactly what JDM TOD unit/parts would be needed to do a conversion?

I believe our JDM TOD boxes are totally different. They are made by Aisen (spelling?) and not the same as the brand you use.
That is why we get all the goodies like -
2wd
Dipstick
Fill tube.

Now that you guys are green with envy, I will retire into my bunker down under.

Of course the down side is - we can't buy any bloody parts for ours!!!!

[PK]

Sorry guys, just noticed I was on 13 posts.
Can't leave it that way - my TOD might fall out on the way home.

PK

[taylorRichie]

We've got the concept proven...

We're now working out what will be best for everyone? Do you think we need the ability to "fine tune" to an exact percentage, or is: 5%, 25%, 50%, 100% enough?

What do you think?