MUDRAT's Manual to Auto conversion thread

Ben · Post by **Ben** » Tue Jan 03, 2006 9:20 pm

MUDRAT wrote:Yeah I'm seriously considering . . . I have seen aftermarket Torsen-type front LSDs for Subies and didn't some of the STi Imprezas come with front VLSDs?

Coupled with the Haultech traction control it should make a formidable beast!!

If you had a torsen diff you wouldn't need traction control as they stop driving the wheels with no grip and divert it all to the wheels with grip.

Would be cheaper to go and see haultech and have them custom build you a traction control in 3 days though...

MUDRAT · Post by **MUDRAT** » Tue Jan 03, 2006 11:38 pm

Having had a mate that got Sam Keck to install Haultech on his 2005 Ford Courier, I'll be stuffed if I hand over my car to those butchers. They can send me the pieces and I'll sort it out myself thanks.

I know with Tony it's a different story, but Overkill should think about changing their name to Keel Over.

smoov · Post by **smoov** » Tue Jan 03, 2006 11:40 pm

sorry to sidetrack here, but whats the go with overkill??

MUDRAT · Post by **MUDRAT** » Tue Jan 03, 2006 11:48 pm

Overkill = Sam Keck and a 240 volt welder and a heap of stuff Tony Robinson is letting him flog.

Overkill 4x4

vincentvega · Post by **vincentvega** » Wed Jan 04, 2006 5:18 am

steve_rising_sun wrote: The planetary boxs is full time AWD until you power solinoid C. You then get full time 4WD so its back the front to a NA box
The planetary gearset works the same as a Pagero Super Select or Rangie ie drive is transmitted through the rear until the rear 'slows' ie a corner causing the third member to 'roll over'
Do it Muddie I am
Steve

Steve you are a deadset legend. thats exactly what i wanted to hear. So the planetary (or VTD as Al calls it) gearset operates just like any other open center diff AWD, until the dutyC solenoid is driven to limit the amount the center diff can slip.

So, if we now use a NA TCU to drive this box we get a normal open center diff AWD on road (just like a pajero, land bruiser etc etc) and then when we dirve the dutyC solenoid with 12V we get a locked center 4WD.

This sounds like an unreal setup for an offroader. As soon as i get back into the country im going to have a serious look at this, im thinking the cheapest way out is to simply bolt a planetary rear coupling to my NA gearbox, and fit a rear LSD while i am at it with no more fears of burning my center clutches out (ala twinkles...)

vincentvega · Post by **vincentvega** » Wed Jan 04, 2006 5:38 am

jzk25 wrote:We need to confirm some facts here before people get the wrong ideas into there heads and waste there time/money.

I am not an electronics expert but I am a Subaru expert . I have also dealt with all types of subaru autos as well as swapping transfers between boxes and monitoring the solenoid activity with the select monitor.

Al I am an electronics expert, and i have a fair clue about subarus aswell (obviously nowhere near your experience though). I am sorry mate but you have got this one wrong.

If you have a solenoid failure on a non turbo car without VTD you are left with fwd only, this would equate to having 0v to the solenoid.

I have a 91 NA liberty auto. Non VTD. Using an oscilloscope, I have observed the TCU controlling the solenoid whilst driving my car, and also a Gen1 turbo auto and the output is the same:

0V at the dutyC solenoid LOCKS the clutch packs. 4WD
12V at the dutyC solenoid OPENS the clutch packs. FWD

I can guarantee this 100%. I have modified both of the above cars with a switch for locked 4WD, and a switch for FWD. The sand flying out the back of the car when im in the dunes is a pretty good indicator that i am NOT in FWD! And the front wheel burnouts i can do when i flick my FWD switch are also a pretty good indicator im in FWD!

I have never had to replace a dead dutyC solenoid but if a dead solenoid does infact equate to 0V at the solenoid as you say, then a dead solenoid will result in locked 4WD. The only thing i have seen result in FWD is burnt out center clutch packs. I have seen this happen 3 times (boosted motor + idiot driver + 3000RPM stally...)

If you have a solenoid failure on a turbo car with VTD you are left with a locked driveline, this would also equate to having 0v at the solenoid.

So applying 12v to a VTD car removes the rear drive bias.

I have had no experience doing this but steve has - and he seems to think that 0V at teh solenoid does not result in locking the driveline.

Applying 12v to a normal transfer gives a locked driveline.

This is incorrect.

The thing with a VTD transfer is it has a centre differential as well so it is still awd without the clutch pack operating but it is like an open diff, the drive will go to the pinion with the least traction.

An open center diff AWD is fine for onroad. We are not talking high performance road cars here, they are all lifted monsters with chunky tyres that dont handle real well anyway. Your still going to have tons more traction than a FWD car.

vincentvega · Post by **vincentvega** » Wed Jan 04, 2006 5:44 am

MechaWagon wrote: Is this what the auto in my Gen III Liberty is? No wonder I can't get the thing bogged...

yep exactly. the TCU control of the rear drive is really strong from the factory. In dave's old lib with the TT engine, he hada 4WD lock switch fittd but he never needed to use it as the rear drive was so strong anyways.

Planning any trips to brisbane soon? I would love to have a look at your car with an oscilloscope

Actually this brings up another interesting point. Bens sedan is a 99ish? EJ20 NA AUTO, however it has VTD. If you could get your hands on this TCU you could have proper control of the dutyC solenoid AND have teh correct shift points for a NA motor.

Maybe you should convert your lib to manual ben, and use the TCU and auto box in your basher!

jzk25 · Post by **jzk25** » Wed Jan 04, 2006 10:24 am

Yep, I got it wrong. Spent a bit of time yesterday checking out transfers and now see where I went wrong. I thought the solenoid was an apply solenoid not a dump solenoid.

Re 99 on boxes. There are still VTD and non VTD boxes. Only WRX and TT autos have VTD(TT also has tiptronic which is a different valve body and extra solenoid). Aus GT fozza's don't have VTD which is strange seeing as it is sort of an offroad vehicle. The later NA tranfers still work very well though, gen 1's were the only real problem cars.

I agree VV that using a VTD box in the way Steverisingsun describes seems like a perfect compromise for an offroad type vehicle, wish I had of thought of it.

Just curious as to how you guys were planning on operating the rest of the gearbox? As in wiring in a TCU etc.
It's worth pointing out that any gen 2 on engine can be run happily with a common as dirt TT TCU and a VTD box.
Mudrat, is your engine a gen 2(I though it was?)

vincentvega · Post by **vincentvega** » Wed Jan 04, 2006 10:47 am

BYB-01 wrote:What is the need for this solenoid mod? Is it to stop that slipping between front and rear that Twinkles car is so good at? If so, didn't the later model boxes sort that out as you have said? What would be the need to do it if that is the case?

on the early clutch type boxes:

the solenoid mod that my car and scott's has lets you lock the center clutch so you get 4WD. problem is the clutches are pretty small and they can only hold on so strong. When you saw scott burn his clutches out at DI he was running extra clutch packs in there and everything, yet his stally let him still burn them out. They are the weakest link in the early AWD driveline

the later planetary boxes:

dont seem to have this problem. the rear drive is far stronger than the earlier boxes, when used with the matching TCU. Why we are talking about playing with the dutyC solenoid is that you could use an early (and dirth cheap) NA TCU to control the later gearbox. The problem is the early TCU cant properly drive the later AWD, so you haev to have a switch wired to lock the center diff.

The other advantage of using the NA TCU is that the shift points are matched to the NA engine, and also they are designed to work with the TPS sensor off the early engines. the later TPS sensors are inverted...

vincentvega · Post by **vincentvega** » Wed Jan 04, 2006 10:58 am

jzk25 wrote:Just curious as to how you guys were planning on operating the rest of the gearbox? As in wiring in a TCU etc.
It's worth pointing out that any gen 2 on engine can be run happily with a common as dirt TT TCU and a VTD box.
Mudrat, is your engine a gen 2(I though it was?)

In my car, i think all that would be required would be to fit the VTD transfer housing, or if my current gearbox fails then a complete VTD gearbox, and the stock NA TCU does the rest. I would just leave the dutyC solenoid disconnected from the TCU, with a switch to apply 12V for lockup 4WD. The fault code the TCU spits out is easily fixed using a 15R resistor as a dummy load. (i do this with my current 4WD lockup switches)

Now that we have established that this will work, we should probably look at mudrats car specifically. I think its a Gen2 motor running a Gen1 ECU and sensors? (is that right muddy?) If so then a gen1 TCU and loom is going to be the way to go, as the TCU will match the gen1 TPS. Then just wire it up as i have described for my car.

Being an L series, muddies car isnt going to ever have full TCU controlled AWD, as the in dash speed sensor is going to be missing. This could probably be fixed by adding another speed sensor, but you would have to do some research and make it match up with the factory lib sensor.

give us your specific info muddy

MUDRAT · Post by **MUDRAT** » Wed Jan 04, 2006 11:25 am

vincentvega wrote:give us your specific info muddy

5'10", brown hair, blue eyes, medium build . . . oh you mean the car!!

Originally it was an 11/1987 GL sedan registered as an '88. The original engine was the carby EA82, can't remember the model carby but just your average automatic choke Hitachie.

The engine is an 6-bolt (???) 1999 Japanese import SOHC EJ20 that's running a full loom and computer from about a 94 or so EJ22 Liberty. So it's running MAF and no vehicle speed sensor.

That's about all I can give you? What else do you need to know?

jzk25 · Post by **jzk25** » Wed Jan 04, 2006 11:48 am

A 1994 ecu should be gen 2 with a 3 wire tps. Is that what your engine has?

You can hook up the speed sensor from an L series to an EJ ecu/tcu. I have done this before to my mates EJ25 LS. The reed switch is in all the LS speedos, you just need to add an earth and signal wire to the ecu.
I would recommend the use of a gen 2 tcu in any case *if practical* because the programming is much much better than the early cars, this is regardless of VTD or not.
If you are purchasing an auto, do not go anywhere near a gen 1 box, they are horribly unreliable. Gen 2 onwards are fine. Sunspares do not sell gen 1 boxes unless people insist on them or if they have rebuild stickers all over them. They really are rubbish.

MUDRAT · Post by **MUDRAT** » Wed Jan 04, 2006 12:42 pm

Yes I'm pretty sure that's what it has. My car's not here today so I can't say for sure.

Thanks for the tip re: Gen 1 'boxes, what makes them so poor?

jzk25 · Post by **jzk25** » Wed Jan 04, 2006 12:56 pm

I guess it's like any first gen model with it's teething problems, the gen 2 boxes are the same box in design but have virtually no faults apart from duty sol C failure. The tcu is a lot better also so the overall package is greatly improved.
Gen 1 boxes are also getting very old and hi km too so failure is imminent anyway.

daza · Post by **daza** » Wed Jan 04, 2006 1:35 pm

<bad us accent> Yawl shoulda seed this ere aready... http://www.ultimatesubaru.net/forum/sho ... e=12&pp=10</bad us accent>

stamp_licker · Post by **stamp_licker** » Wed Jan 04, 2006 8:22 pm

what year r the gen 2 boxes?the ecu manual and auto r they the same?
L speed sensor location :When you pull out L series cluster, look at the back where the speedo cable goes in.

Just to the left of it there are 2 holes where it looks like a screw can be inserted.
One will be labelled 100k (this is for the jap spec one which have a chime that goes off when you exceed 100km/h).
The other one is for the speedo signal output.
Insert a screw like the others on the back of the cluster & trace (with a multimeter) that circuit back to the pins (its not a straight run)

I'm not 100% sure though whether all the speedo mechanisms have the output built into them tho

Ben · Post by **Ben** » Thu Jan 05, 2006 11:09 pm

Has anyone got a price on a vtd boc, tcu, tc and harness yet?

I need some sort of box - the L one in my wagon is having 'issues'...

jzk25 · Post by **jzk25** » Fri Jan 06, 2006 10:15 am

I've got a VTD TT 4.44 box with 80k on it and the tcu and wiring. Also have a 4.11 gen 2 NA box originally out of my TT wagon that was in good working order, it has a TCU as well. Not sure on value as I haven't really thought about selling them, they were just spares for our cars.

I believe Steverisingsun has a TT box for sale also.

Outback bloke · Post by **Outback bloke** » Fri Jan 06, 2006 11:13 am

Hi-jack. Ben, what is wrong with yoru manual? How much for it when you yank it out?

steve_rising_sun · Post by **steve_rising_sun** » Fri Jan 06, 2006 9:50 pm

I hate to ask a silly...... but what does VTD stand for? I hope the V is not for viscous.
Steve