A70 Circuit Racers - Which Diff?

ReQuieM

malicious.com.au
Hey shane, you were on aussie SF for a bit yeah? I think you rocked up around the time I stopped going... Anyhoo; I have a Torson that I'll be removing in a few weeks to a month - got about 5000k on it from me, if you want it, you can have it complete in pumpkin for $450 +P&P

I'm also in the process of building up an unbreakable (fingers crossed) diff. I have a 2way kaz centre and I've been talking to a local diff builder that builds 4x4 G series for mud crawlers etc. First thing he mentioned is the crush spacer which he has suggested one of his machined billet jobbies, he's charging me about 100-150 (AUD) for the solid spacer, does that seem fair? Seams good to me tho until I read this thread I didn't realise it was such a well know problem or that there was off the shelf parts for it... He did also say that with out replacing it with a solid that the diff would play up again in a shorter period of time, which backs up the previously posted US SF thread and vise-versa.

Also he was talking about clearing the oil galleries and fitting (I believe he mentioned machining to fit) a Mitsu Pajero front bearing assembly as they are a more heavy duty bearing... Anyone had any experience with 'upgraded bearings'?

Also a couple of other things he mentioned, the clutch-packs rarely wear out, generally the cause of diff failure on the G is from the bearings degrading and failing. The shit n metal they shoot off as they fail gets wedged/stuck in between the clutch packs and causes them to slip. 99% of the time he rebuilds a G, he replaces the bearings on the housing, disassembles the centre and clears/cleans it out, machining any imperfections out of the clutch packs them selfs if needed then assemble and adjust back lash.

They guy sounded like he knew his shit and was extremely helpful and not pushy for a sale either, so I have a tendancey to believe him. But I would like to hear what you guys have to think about what I've said, he said? Baring fuck ups in the conveyance on my part! lol

Also has anyone fitted a diff cooler to a stock housing? I'd like to do it as a precaution for when i run on the track, and because I don't want to have to folk out hard coin on the dif again. Whats the best way to approach it? I was thinking of fitting screw in hose fittings to the drain and fill plugs, but will the drain one hange to low on the car? Also how would you go setting up a pump etc?

IJ I might have to be a pest and com have a lot at your set up some time so I can get ideas on the best way to set up one for me! :)
 

ReQuieM

malicious.com.au
Down but not out; How does that one work? it just looks like a finned stack that sitts on top? surely that wouldn't cool the actual oil? Maybe the air in there, but how will that help the oil temps more then minutely? Don't mean to sound... um i donno sus, but I'm not sure how effective it would be? but if it is, then I want one! alot easier then a pump, cooler, lines etc :p

EDIT; just had another look at that thread, the inner bit that extends into the oil would help make a difference but yeah I'm still a bit sus about how well it would work?
 
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IJ.

Grumpy Old Man
Mar 30, 2005
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Down but not out;1103580 said:
My stock 3.73lsd has a cooler on it :wiggle: I have yet to see a pic of a diff that has a cooler like mine on here.

Strange how we got them in the UK, when America has higher ambient temps.

UK LSD cooler
Steve/GroupA has one of those.

ReQuieM;1103588 said:
Down but not out; How does that one work? it just looks like a finned stack that sitts on top? surely that wouldn't cool the actual oil? Maybe the air in there, but how will that help the oil temps more then minutely? Don't mean to sound... um i donno sus, but I'm not sure how effective it would be? but if it is, then I want one! alot easier then a pump, cooler, lines etc :p

EDIT; just had another look at that thread, the inner bit that extends into the oil would help make a difference but yeah I'm still a bit sus about how well it would work?
No probs at all Leigh just send me a PM any time you want to drop over.

The Europe Cooler looks a bit like a thermosyphon setup but I can't be sure without seeing inside one.
 

7MGTEsup

Formerly 'Down but not out'
Jun 14, 2005
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ReQuieM;1103588 said:
just had another look at that thread, the inner bit that extends into the oil would help make a difference but yeah I'm still a bit sus about how well it would work?

I have no idea how efficent it is, but it must do something or Toyota wouldn't waste time/money fitting it. I think it works like the heat pipe coolers you get on processors on pc's.
 

prsrcokr

Motörhead
Apr 3, 2005
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I think the Euros were designed with autobahn abuse in mind. I've heard the cooler is available from Toyota for ~5k!

Doesn't sound like yall have had problems with the Torsen unit though. Don't like the operation?
I really like mine but I'm coming from being tired of wearing clutches on previous diffs. When fluid was changed, it did seem to help grip a little more but would still begin slipping in a short amount of time. The cost of new clutches (9 of them?) was high so I figured I'd try what a fair amount of track guys were recommending.
 

ReQuieM

malicious.com.au
I have had problems with the torson, more from just in the why it works. I hate the way that it decides when it will be LSD or single. I have had small amounts of controlled broken traction suddenly hook up and send you careening forward. Honestly it is the only thing on my car that scares the shit out of me. Its too unpredictable. Plus it bogs down on initial engagement etc.

Thats not including the obvious weaknesses, blowing on hard launch, blowing when engaging to go forward while rolling backward etc etc.

For me, its not worth it, I'll go something that is 100% predicable and be happy! :)

BTW, are you sure you were wearing out the clutch packs and not having the issue that described earlier with shrapnel being caught in between them? It sounds like it if you are changing the fluid and having it preform better and then start to slip again...
 

prsrcokr

Motörhead
Apr 3, 2005
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What's understeer? ;)

I don't see it as not being predictable at all, of course it is a torque multiplier and 0 times anything is 0, if that's what you mean (getting no traction to one tire)

Even in the rain events it's done well but I've had some snap spins getting used to it. I'll agree by design it's not the unit for shock use (drag launch, rolling backward to forward acceleration, etc)
I do find it much easier to control in slides than the clutch type but again that was suspect of failing (pieces of grit in oil, as mentioned it would grip better with new oil but only for a short time, 1-2 auto-xes)
 

IJ.

Grumpy Old Man
Mar 30, 2005
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Only time my T1 bugged me was if it lifted a wheel in a corner, the TrueTrac has a preload pack to prevent loss of drive in this scenario but as delivered it's set far too stiff for short road tires (it's designed with 33" tall mud tires in mind for the offroaders)
 

ReQuieM

malicious.com.au
Perhaps its only the snap spins that I'm thinking off but its still way to upredicable for me. Realistically I might even get used to it an enjoy it but I seriously doubt I will ever really be comfortable with it, plus I'd like a stronger dif so I can not worry about it again.

I'm really looking forward to getting my powerlocker in this week end :)

BTW IJ the diff guy I'm using was saying there is now a powerlocker with (IIRC variable)ramps for the 9" called the powertrak or something... says that all the 600hp sports sedans have all switched over from there goldtraks to the new power traks and loving them... Just in case you wanted to know ;)
 

IJ.

Grumpy Old Man
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ReQuieM;1109815 said:
Nah no link sorry, just going from what he told me over the phone. I can see if I can grab some info and/or linkage for you when I pick up the dif.... monday if I'm lucky :|
Thanks Leigh

SlimLim;1110015 said:
Where do you buy TrueTrac in Aust IJ?
My TrueTrac is a 9" one they don't do one for a stock G Diff.

group a supra;1110021 said:
i have a few diffs with the cooler on top ian i aint broke one yet ;)
Ummmm your fast/powerful car doesn't run so of course you haven't ;)