After doing a 180 degree spin through a hedgerow caused by a driveshaft failure I realised I needed a better solution to the rear end setup of my Triumph Spitfire! I acquired some good used rotoflex parts from a GT6 and was going to use this, until looking at the antiquated rubber donut setup which I didn't think would last very long with the torque my engine will put through them! So a better solution was sought. I got in contact with Nick Jones who had converted his Vittesse to a CV setup using Ford Escort half shafts and outer joints mated to Volvo 340 inner CV joints. his conversion can be found here. Nick had solved the problem of attaching the inner CV joint to the Triumph diff output flanges by welding adapters directly to the diff output flanges, He also retained the original Triumph rear bearings and shim arrangement, which he informed me was a pain in the arse to shim with his setup!

bent and broken bits that aren't supposed to be bent and broken.

I decided to take a slightly different approach To Nick, my conversion retains the rotoflex uprights, wishbones and radius arms. With this I used MGF rear hubs and bearings. The drive shafts are Rover 100, I was going to use MGF shafts but these were 20mm shorter, but identical in every other respect. I expect there are several shafts that are suitable. the inner CV joint is a Volvo 340 93mm Lobro type

I had the uprights machined to take the more modern and stronger Rover MGF bearings, also used on many other cars including several current Lotus models, these don't require any of the shimming nonsense! to make them fit the inner upright had to be machined out straight through, from about 65mm to about 67mm, so the new bearing race is a press fit. The rear of the upright was machined out from about 83mm to 85mm to ensure the new outer CV joint would not foul. On the other side 4.5mm was machined off  to make up for the extra thickness of the MGF hub and slightly different way the bearing sits in the upright, the inner upright also need machining to accept circlips that come with the bearings.

Above shows the CV conversion in place, the round thing on the drive shaft is a torsion damper as fitted to many modern shafts

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