Lotus Elan and Lotus Elan Plus 2 Forums

Hi

I've been offered a set of early sliding spline UJ drive shafts. Beyond condition of splines and UJ's, what else should be checked on them?
Are there any differences in the hub plate between them or are they interchangeable between models?

Thanks

The sliding spline U/J driveshafts are bomb proof ( Performance Unlimited ? ),I suppose Elan and Plus2 ones are of different length ? That's if one can fit them to the elan with tight droop angles ?

Hub Plate ? do you mean the plate fitted to each U/J which attaches to the spiders?

Should be standard...

John

Hi
I fitted a pair of sliding spline UJ's awhile ago.The inboard drive shaft spider?has a different bolt pattern on early S1's to later 3 ear ones as I recall.2 bolt holes line up but not all3!
My terminology may be wrong -no 71 in the shop manual.

For what its worth, I wouldn't use sliding splines on a road car.

The rear suspension on the Elan has a large amount of travel, and as a result the driveshaft plunges a decent amount. Rotoflex accommodates this plunge as well as the angular displacement, UJs can't cope with plunge, hence the sliding spline.

The downside of a spline is that it locks under load, and as a result will lock the rear suspension under acceleration, releasing at the gearchange points. So if you are accelerating out of a bend, potentially the rear suspension will jump at the gear change point as the suspension rebalances when the spline unlocks as the torque is removed. The other issue is that if you hit a bump under acceleration with the spline locked, potentially damaging lateral loads are applied to the wheel bearing and diff output shaft bearing. In period, formula cars used ball splines, which used ball bearings in the spline slideways and didn't lock under load.

I have TTR UJ/splines on my race Elan, but the rear suspension is lowered and rock hard and wheel articulation is very limited. My road Elan has Miller CVs which I believe to be a far better solution (and I would prefer to use on my race Elan if the regs would allow).

My S4 car came with sliding spline U/J drive shafts but also the lower forward tube of the rear wishbones are attached to the chassis with stainless steel cables to limit the amount of suspension travel. Without these the consequences would be serious!! Rubber doughnuts do have some advantages but they are also very expensive now.

...and of dubious quality...


John

I've had sliding splines on my car for 8 years with no issues. The car is not lowered but I do have AVO shocks.
I don't race the car but I have done some track days and spirited canyon drives and I have never had a handling issue or suspension travel issue. I purchased them from Paul Matty. My two cents.
Ken