Performance diff info thread.

For non EFI mechanical discussion
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vlad01
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Re: Performance diff info thread.

Post by vlad01 »

What wheels did the group A run? makes me wonder if I can use VL diff with the walky wheels?
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Dylan
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Re: Performance diff info thread.

Post by Dylan »

17X8

Seems to be a common belief that the VN Group A ran the VL diff as a straight bolt in but they had different wheel tub from factory. That's in factory HSV paper work.
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vlad01
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Re: Performance diff info thread.

Post by vlad01 »

yep, that size ain't happening lol
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gtrboyy
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Re: Performance diff info thread.

Post by gtrboyy »

Yep vn group a was vl diff with modified inner wheeltubs....got polaroids from 90's of my one with chasers on back a nice distance inside quarter lol

Wouldn't be hard to fit decent sized wheels with adjustable panhard & little bit of hammer/dolly work.

Never heard one about v8 diff being slightly narrower than v6 diff assumed they were all the same having mix 'n' matched broken axles from all different models.
vp304
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Re: Performance diff info thread.

Post by vp304 »

post bump from the dead
Looking at one of these
https://www.ebay.com.au/itm/186186512252

Saw some people talking about these chinese tru trac style centers for m78 diffs
How are yours going still twin spinning ? working well no noises etc ?
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vlad01
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Re: Performance diff info thread.

Post by vlad01 »

Yeah, the KAAZ center has been great but I have not done a lot of ks on them. Maybe 4-5k since the car build some 6 years ago. I don't hear it at all in terms of clutch chatter.

if I was to do it again, I'd probably get Harrop to install one of their centers. I've heard nothing but good from their version of the Eaton trutrac and I would prefer something that behaves more like an open diff in "normal" driving conditions, the KAAZ is kinda closer (if you squint) to a spool than the trutac is in normal driving, but both lock up at high loads with the trutrac being more seamless where the KAAZ is closer to on/off.
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VK_3800
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Re: Performance diff info thread.

Post by VK_3800 »

I have a Harrop-cased Eaton Truetrac; note these never actually lock, just transfer torque around provided there is some amount of traction. But good for street driving and laying down power out of corners for that very reason, it's quite cool getting forward drive while one wheel is spinning.

Regarding the cheaper version I definitely would have tried this if they were available at the time as the Harrop option you basically pay full price, twice! No idea on longevity but I would think if it works initially then there's no reason why that would change over time as the gear design doesn't wear like a traditional LSD.
brindo
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Re: Performance diff info thread.

Post by brindo »

I have one - see post a few pages back with the part numbers of the super shims to make installation a bit easier.
Its done a lot of miles and has been working well no issues.
But that price in the link you have is very cheap. They are usually double that price or more. Might be a Chinese knock off of a Chinese knock off. For the price though would be worth the gamble.

I have another one in the shed waiting to go into a diff with some lower gears when I get the time.
immortality
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Re: Performance diff info thread.

Post by immortality »

I almost want to test one of those really cheap units for shits and giggles.

The problem I see is that most are listed for M78 and are no good for the IRS model cars as they have an extra groove in the bore for the stub shaft retaining clip. The Harrop doesn't have those either so it means it's no good for IRS. I have a Harrop that I want to use in my Senator but I've not found a solution yet :( except stripping the diff and taking it to a machine shot so they can cut the required groove.
vp304
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Re: Performance diff info thread.

Post by vp304 »

I have a m80 irs with eaton tru trac in another car for many years has been good.

The m78 is for my vr ute so is a kind of budget build and is why i was looking at the chinese center

Brindo is yours the mace chinese version or this cheaper again chinese version
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