Lotus Elan S4 - Upgraded Driveshafts [Spyder?]

Overview of the Spyder (despite me saying Vegantune in the video) driveshafts on our Lotus Elan S4.
As standard these cars come with Rotoflex couplings on both ends of the driveshaft, as was used in F1 at the time of the Elan’s birth. However, these will struggle over time living in the harsh environment under the car, they’re damaged by jacking the car up with the suspension droop putting massive strain on the rubber and also rubber just generally ages over time.
This car has the upgraded Spyder solution. The inner Rotoflex coupling is retained, so as to allow the standard drive flanges to be used on the diff, rather than needing to upgrade them. The outer coupling is replaced with a CV joint. Length adjustment is dealt with via a splined sliding section in the middle of the 28mm chromoly steel shaft.

[@pharriso951]

Malcolm, I enjoy your posts. The outer joints are not constant velocity (cv) joints, they are universal joints (UJs) as on a propshaft; CV joints allow plunge so the centre slide joint would not be required. That piece assembled onto the Diif drive flange is for anti-flail. If the doughnut fails it spins out causing damage to the bodywork and/or chassis. That extra piece keeps the end of the driveshaft in position, stoppping it from flailing.... clever!

[@andrew8502]

interesting video. I recently purchased an elan and found it to be fitted with inboard UJ's and outboard doughnuts. I had never seen this setup before. Now i know they are Vegantune parts. Though, mine are fitted opposite to your car. My UJ's are inboard (diff end) and the doughnuts at the uprights.

[@frankhoward7645]

I don't understand the harshness effect. What's harsh? Modern FWD and 4WD cars have CV joints only. I don't hear owners complaining about harshness.

[@Type36]

Have you driven an Elan with CV joints? It’s an improvement over the rubber Rotoflex joints!!!

[@melvynwoodman5787]

Definitely spyder parts. They still supply these but I can’t see the point when you can get elantrickbits or mick Miller all metal cv versions. The doughnuts are not that cheap and definitely not an easy replace or long life item. If the cushioning effect is a requirement it would be better incorporated into a prop shaft using rubber in compression only.