Quaife ATB

[coombsie66]

Right boys i need your help!

I just managed to eventually get our old diff out of our old Formula Student car. Its a Quaife ATB from a Fiesta RS turbo i believe (as that was the smallest they do).
After dissasembing it, i still dont understand how it works. Ours was pretty stiff and miss-treated. And as the application is soo light weight it was never slipping, so we may as well have had a solid rear axle!
In the centre of it are a set of 6 slightly conical washers, which sit inside the splined retainers in the central wheel (which is strangely shaped, the helical gears dont mesh into it, mearly sit into some 'cups' around its circumference).
It ends up that one of our splines retainers was shot to shit and fell out in 4 pieces when we took it out! (where im gunna get another fuck knows)
But anyway, i have an incling that the pre-load that these washers in the centres exert on the two large central planet helical gears at the top and bottom, determines how easily the diff will allow the inside wheel to turn (ie when your turning a corner and dont want the inside wheel scrubbing).
Does anyone here know if that is the case?

Has anyone had any experience with quaife ATB's? As im thinking that due to it being so fuckin heavy, and if we cant get it to slip more easily (or find a replacement splined retainer) that we're gunna have to go elsewhere for a diff. And thats mucho deniero and we dont have a huge amount of time left.

Cheers,

PS apologies to those who dont know about the diff, that paragraph has got to have been mind boggling.

[jon_s]

have you tried posting on www.fiestaturbo.com?

[mindgam3]

or try pistonheads.... there's a fair few mechanics/engineers on there

[coombsie66]

Thats a good idea boys. Thought i'd come closest to home 1st tho

[findleybeast]

any photos of the diff disassembled? though I don't know how this one works it'd be interesting to see

[jon_s]

Link a huge pic:
http://www.croix-chapeau.com/monsite...ciel%20ATB.jpg

some bits of it I believe

[coombsie66]

Right, although i have no idea how it works, i realise what the bits kinda do now, so no worries on this thread no more, unless sumone knows the ins and outs of the ATB.

The ease with which the diff slips can be set with those washers and the splined retainers (at teh very centre of the diff) by altering their orientation. So i shall have to have a fiddle.
Oh and i rung quaife, the diff is still in production and the replacement piece i need should come to about £15, so not bad all in all.



Another update: after installing the replacement part today it ends up that the faliure and shit performance of the diff previously was down to incorrect orientation of the broken splined retaining collar during assembly previously. (hence it was forced into places it wasnt designed to go, locked and the shock load it experienced when it was unlocked shattered it).
The new retaining collar is installed correctly, and it looks like the alterations in preload actually have an effect now!!

I look forward to utilising it on track soon!