16 replies to this topic

[Lenhamracer]

Dear members

 

I am currently running a Tran X MK6 LSD on my rally car and I find it hard to keep a straight line on loose surfaces and very hard to drive on tight bends...you need both arms!! Last time out before christmas we ended up in a ditch after accelerating too much and going from right to left and back...see picture

I was thinking of going to an open X pin diff but it might be best to go to the Quaife ATB diff. What do you think? Any experience?

Thank you very much and all the best to everyone for 2022

Attached Files

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Edited by Lenhamracer, 12 January 2022 - 06:39 PM.

[nicklouse]

Never been a fan of the way a plate diff works in a FWD car. Going from locked to open until. It slides enough to lock again.

 

Cooperman runs a fully open diff IIRC.

 

I think an ATB will be my next diff when the JKD gives up.

[cal844]

Fully open (Cooperman recommends this in a rally application) or ATB will be better in a fwd application

Edited by cal844, 12 January 2022 - 08:27 PM.

[Spider]

I'd say the slipping torque on your Trans-X is set too high for off road use.

If you'd like something that will give the advantages you are looking for from the LSD, without the downside, fit an ATB.

After running these in a few of my Minis and Mokes (the Mokes do mostly off road stuff) now, I'll never ever go back to an open diff.

[Lenhamracer]

Thank you, seems really the way to go. The car was equipped with an old style salisbury lsd and that was a very hard drive. I went to the tran x and it is better but still hard especially on days were you do 400km on tiny roads….

Will keep you updated. May be I start a new topic under „projects“ for the car.

[Gaz66]

I had a salisbury in my grasser which I thought was excellent. When the grasser went pear shaped the salisbury found its way into a road car which was a totally different kettle of fish.
I experienced just what you are now, really severe weaving under acceleration but unbelievable grip in corners as long as you trained your brain to work the opposite way round, eg keep your foot to the floor and hang on rather than backing off because your expecting understeer.
Would I have another plate diff? Yes, thats exactly what I plan for the next project but the plate diffs of today are better than the old salisbury ones from what Ive been lead to believe.
If your stuck with an old salisbury there are ways of taming it by resetting the preload and changing the ramp angle.
Paul hickey does a good explanation of plate diffs and how to set them up in one of his videos on youtube.

[r.tec]

I just love my Tran-X

[PoolGuy]

I just love my Tran-X

That picture highlights another reason for going with a Quaife ATB, you'll never see it once you've fitted it, they're bomb proof and don't need any servicing.

[r.tec]

No, this picture was taken just for fun to see what is inside. I dismantled the diff only to take this photo. It is in no way an argument against Tran-X. The opposite is true!

[PoolGuy]

No, this picture was taken just for fun to see what is inside. I dismantled the diff only to take this photo. It is in no way an argument against Tran-X. The opposite is true!

Apologies I thought it was the Trans-X that needed regular servicing. 

[Cooperman]

Although I started rallying in Minis in 1961 (yes, really!), and have used everything up to very full-on Cooper 'S's, I have never been able to get to grips (lol) with any sort of LSD. I have tried many, but I always struggle to go quickly on gravel or on twisty tarmac.

It's not only me though. My very good friend, the late Russell Brookes, was persuaded to do the RAC Rally in the 1990's in a Cooper 1275 which had an LSD. He reckoned it cost him many minutes due to its unpredictability on gravel. He said the car did not feel like a Mini at all, at least not like the rally Minis he drove at the beginning of his career.

My son did an International Historic rally in Belgium as co-driver in a Mk.1 1275 S fitted with an LSD. They entered a tightening left hander a bit to quickly and the front outside wheel went onto the grass. The driver fed in full power, but the wheel on the tarmac, i.e. the inside wheel, gripped then road and the car shot off to the right and into a ditch - rally over. Speaking with my son later, he said that if we had been in  my car at the same speed in the same corner, when I had realised I was going a bit too fast I would have lifted off then as a bit of oversteer started I would have added full power and the outside wheel would have spun-up on the grass and keft 'the front in front' and the car out of the ditch.

It was always considered the case that LSD's were for racing/hill climbing/sprints, etc.

However, and there is a big however, modern rallying does not use the old technique of keeping th car a bit 'fluid'. With very comprehensive pace notes the cars go less sideways and 'racing' lines are more the way to go. Especially on tarmac with these full notes, an LSD may well give slightly better times, but that's fine until a small mistake is made when right on the limit, then it can easily go 'pear shaped'. 

I always use a cross-pin diff for reliability and find that the car drives and handles in a very friendly way on all surfaces.

I hope this rather long post is helpful.  

[Lenhamracer]

Thank you very much fort all the information. I think I might try the ATB but I have to save some cash first. It is quite an investment as I need a new set of crown and pinion as well and the adapters for my hardy spicer driveshafts. X-pin is not available currently anyway....

[GraemeC]

ATB uses a standard CWP.

You might need to relieve the case very slightly for it to fit, but it really isn't much.

[imack]

I've not had to remove any material from my 22g1128 casing to fit an ATB.

[GraemeC]

Hence the 'might' - I've had to on some and not on others, guess it just depends on the casting.  Most (but not all) of the ones I have had to fettle have been rod change.