Lotus Elan and Lotus Elan Plus 2 Forums

Besides the Lotus differential what sliding spline type final drive options are there for the Elan? I am prepared to do frame modifications. Thanks, Roy

You can get driveshafts with two CV joints or one CV joing and one rotoflex coupling. I think the sliding spline drive was not that popular because it was supposed to lock if the back end got too high or the suspension dropped too much (going the top of a hill). The double CV joing driveshaft seems the most popular, especially given the cost and quality of some of the rotofles couplings around at the moment. They Sue Miller or Tony Thompson in the UK for the double CV driveshafts.
As far as I am aware they need little modifications if at all. Some reruire the 'anti flail' pins to be ground off if you car is fitted with them.

Doesn't the Spyder conversion use the final drive off of another car? What kind of car can I use for donor parts to come up with a final drive solution? I've driven the rotoflex option and I don't want it. Dual CV's sounds good to me. I don't have anything right now so for me it is probably just as economical to choose a non Lotus final drive assembly. Thanks, Roy

Roy, when you say "final drive", I believe you mean drive-shafts, and not the differential.. (?) .
I have tried the Spyder version, with one donut and one CV joint, and it works well. It does also have a sliding spline , and requires some greasing from time to time. The TT-shafts with two CV joints are very nice items, but I believe Mr. Thompson has made them with racing in mind....They require quite frekvent greasing. TT will also tell you to change your outer and inner shafts as well at the same time, as they may not be (!!) of the same quality steel as the new shafts. What is really nescessary for the street may be discussed, but I believe TT is right when it comes to racing!
Dag

If you decide to go for the Spyder hybrid driveshafts (and are in the UK) I will have a pair available soon.
Rick

I seem to remember reading somewhere (?) that the CV joints are ex VW?
I think the driveshafts are specifically made for the Elan so you can't just get them off another car (in true Lotus style)

Carl

(There is also a company on OZ who makes them...)

From what I'd heard after I bought the full CV joint setup from Dave Bean Engineering here in the US, the whole setup is VW Bug; though the halfshafts have been shortened - I hear this is easy to have done here in the US, there are enough hotrod builders that get this kind of thing done all the time. When I got the halfshaft setup, my then boss positively identified them as being VW Beetle, he'd worked on many of them - the only real tricky part was the aluminum adapter plate which converted the 3 bolt Rotoflex pattern to the 6 bolt CV joint patter; and I opted for the custom made diff output shafts which mate right up to the CV joint - my output shafts were showing signs of twist, so were getting ready to break anyway! I'm very happy with the CV joint setup, completely got rid of the yo-yo effect of the Rotoflexes.....though my car did have the early ones without the extra stiffener plates!
Dave
lotus026

Roy,

I don't know whether you mean the drive shafts or the differential itself. If the latter, I think that a number of Ford options exist from their models of a similar time period. I have heard of people fitting Escort diffs, although the final drive ratio will differ.

If you really did mean the drive shafts, then I have fitted TTR sliding spine twin UJ type drives and have had no problems, in fact I rate them. I am suppossed to limit the suspension travel, or grind down one of the the nuts on each flange but this is hardly necessary. The rationale for this is that at full suspension extension, the connecting nuts come into contact with the UJs. However, on the TTR version, this is only marginally so and I have found that it never happens on the road. How many people do you know that go over a hump-backed bridge at such speed that they take off? If you are one of them, then CVs may be for you!

Matt

I have the Dave Bean CV joint system on my S2 and they have been trouble free since installation. I believe they come with uprated differential output shafts and I also replaced the axles with up rated ones. I have found this to be a very nice trouble free system and believe I have been off the ground on the up-hill right hander at Lime Rock Park in Connecticut, USA, without any noticeable consequnces. The humble VW CV joints seem to work well.

Bill