Lotus Elan and Lotus Elan Plus 2 Forums

Sorry but this has probably been done to death, but what are peoples experiences of replacement driveshafts? The Mick Millar CV sounds good but will it break my diff? TTR's? Spyder?
Can you make your own? I seem to remember seeing somthing about this but can't remember where.

Thanks

Jack
:blink:

Jack, don't worry about breaking the diff. It's the stub axles that will take the beating. The CV jointed axles are the way to go. Have had mine for over 20 yrs with no problems to speak of, with plenty of hard launches for slaloming.

Greg Z.
'72 Sprint

Greg,
I've almost finished making up a couple of sets of cv shafts, I know you and Arno made them up (from previous posts) I have also made them up with VW shafts & joints, the shafts were shortened, joined with a male/female fitting & sleeves. (as you did)
Now the guy who welded the shafts suggested I should have the shafts heat treated, did you have yours heat treated after welding?
Regards Brian.

Brian,
No, I didn't. I realize that the original heat treatment (if any) is lost with the cutting and welding but the type of joint more than made up for it. I'm anxious to hear your opinion of the whole setup after installation.

Im thinking of ditching the donuts also but one thing concerns me.

Do CV joints allow any telescopic movement of the driveshaft? As the wheel distance is governed by the rear suspension arms the shaft has to change length as it moves up and down to keep the same diff to wheel distance as the angle changes. The donuts allow some in and out movement.

Thats why I like the TT sliding spline approach or have I got it totally wrong!

Dave

s4 elan 1970

Dave,
Absolutely. Think about it: Just about every car on the road today uses CV joints. That's why a U joint needs a telescoping end to it because it can't. A CV joint will. Put one on each end and you've got a couple of inches movement.

Greg Z.

Thanks for the help on the cv joint "length" issue. But I have dug a bit deeper and there are two types of CV joint. Plunging and non plunging. One allows some in/out movement the other doesnt.
Does anyone know if the mick miller ones "plunge" coz if they do ill take the plunge and buy a set.

Sorry for the pun
They are discribed well on this website .

<a href='http://www.bondauto.com/templates/school.php/article_id/28' target='_blank'>http://www.bondauto.com/templates/school.p...p/article_id/28</a>

cheers

Dave

Dave,
Yes, the MM cv's are of the plunging type.

Greg,
A couple more questions on your set up,
The MM conversion uses I00mm cv's and do not require a "droop" limiting device as the 100mm has enough angluar movement.
What size C.V.'s did you use and did you use a limiting device? i.e. a strap or shortened springs/shocks, I am using 100mm on one set and 90mm on the other and do not know if the 90mm has enough travel.
Regards Brian. :rolleyes:

Good question. I got mine from an old VW bug about 30 yrs ago. I don't have a droop limiter although I wish I had. At full droop, the boot is really stretched and I've had them pull out of the swedge fitting a couple of times. A real pain to replace. I made certain that the replacement boots were of VW quality. I haven't had that problem in the last 10 years or so but I check them after spirited runs.

Greg Z.

I would think that you would want plunging-type at one end and non-plunging at the other end. You wouldn't want the shaft "floating" between two plunging CV joints, rather have it anchored at one end.

Hi Rich,
The MM conversion uses plunging cv's at both ends, the VW Beetle (bug with double jointed axle) and the VW Bus (kombi) also use two plunging cv's. As far as I am aware this system is also used on the Ford Sierra, BMW's and the Lotus Esprit, the "float"of the shaft does not seem to be an issue.
Regards Brian. :rolleyes:

Hi,
I am in the middle of fitting the TT sliding spline...
They seem well made, but either need a droop limiting device (or TT's shocks) or a bit of grinding on one of the UJs..
Cheers
Tim

Greg,
Update on cv conversion, I finished & fitted one one set (100mm cv's) no wind-up,
no surge, no kangaroo starts, feels good with positive take up on drive, slight binding on full droop but is getting less with use.
Regards Brian.

Sounds like you like your conversion, Brian. Car drives somewhat normal now, doesn't it? Glad you like it. You won't be disappointed.

Forgot to add that my adapter plates are aluminum and the bolts holding the cv's to the plate were always coming loose and at one point, an axle actually fell off the plate and jammed on the A-arm. Good thing I was going slow at the time. Since then, I've loctited AND safety wired all the bolts. No problems since.