Hi folks - i have seen a tempra 4x4SX which seems to have a lockable rear diff.
Not a UK import i know - but lancias and alfas may have had the same axle - so does anyone know much about these.

dash mounted switch says REAR DIFF LOCK, which kinda seems easily understood, but with Fiat you never know...
torsen diffs are listed for other tipo platform cars - but these wouldn't need a switch would they?


my reason for asking - autocrossing could be fun if the diff could be locked for an event etc - then left open for normal driving on dirty country roads where an open diff would be safer than a LSD.

i have an old Sei which is going to get a heart transplant soon - 1.3xflow finally coming out.. megasquirtedGSXR600Tbs 1.8zetec going in i'd like to think the car should be a little quicker soon


[Edited on 15/9/06 by blankczechbook]

A locked diff is different to limited slip diff. It locks the wheels together completely so they turn at the same rate all the time to get you out of trouble in the rough. On tarmac it would make cornering a nightmare with the wheels spinning on the inside and pushing the back end out.

quote:

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Originally posted by Peteff
A locked diff is different to limited slip diff. It locks the wheels together completely so they turn at the same rate all the time to get you out of trouble in the rough. On tarmac it would make cornering a nightmare with the wheels spinning on the inside and pushing the back end out.

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yep Pete - thats the idea

but it'd be switchable if i have understood the system correctly...

so loon it about carparks in autotests and drifts... then open the diff for blats in the countryside..

I'm just saying it will be no help with a locked diff on anything that involves corners. If you were drag racing it would be a different story. Check up on spool diffs. Your car will hop round like a demented kangaroo if you turn the wheels on solid ground with the diff locked, not give you any control like LSD.

quote:

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Originally posted by Peteff
I'm just saying it will be no help with a locked diff on anything that involves corners.

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And drive flat out all the time with the tyres smoking to reduce grip. The prop will also suffer and the clutch will last a matter of minutes. Do it as an experiment but don't expect brilliant results. Buy the Tempra and use it for the back axle, it's never gonna happen I doubt an old Fiat axle from a mainly FWD car with proportionate drive to the rear will take the output from the 1.8 zetec you are thinking of fitting anyway. There's one on the Polish autotrader site get your hand in your pocket.

i think these axles were used on the lancia thema integrale and the 155 q4, and they are on the 2litre16v tempra...

but i am not sure about specs - which is why i was asking if anyone knew any more useful info about them.

I think autotesting probably has a bit more to it than just leaving black lines around cones.. and it helps to swing the back about a bit.


i also live in europe so these axles are slightly less rare than they are in the uk..
sierra diffs are big, quaife diffs expensive.. so i am looking at ALL options.

sierra diffs are heavy too...

There's a Lancia Delta diff on ebay here . It looks like it uses a torque tube instead of a prop so it might be a bit of a job to adapt it if the thema uses a similar one.

[Edited on 18/9/06 by Peteff]

yep, that looks like the same diff - but can't see any electrics for locking or hydraulic/air connections, so I assume it is a torsen diff, in which case i dunno what the dash switch does - unless it locks the centre diff instead...

but as you say - it is torque tube, which isn't insurmountable as my Sei has independant rears already..
..but it is more hassle - which i have enough of for the moment, so will shelve the idea and wait for the owner of the tempra to scrap it - and then gift me the diff...

idea put on hold - thank you for your time - for now :-)

I doubt you could lock the rear diff on a road car, more likely would be to engage rear diff. Most road 4x4s are FWD 99% of the time, with a switch to 4WD if needed (mainly electronically controlled) I suspect the switch in question does this.
(Ihave been known to be wrong though )

that's the case with the switchable ones.

off-subject but the Sierra 4x4 is obviously permanent 4x4, approximately 66% torque split to the rear and 33% to the front. One of the great transmission designs of its time, designed by Ferguson, (FFD) and first fitted to the Jenson interceptor in its basic form, then redeveloped for rallycross capris, then some converted capri roadcars, then for the sierra XR4x4. Has LSD's at the rear, and at the centre, with an open front diff.

of no relevance here but interesting nonsense all the same!