[PeterAllen]

I've actually found some axles on ebay - 15 5/8" (400mm) - and the good news is the splines are 3' (75mm), so there should be no dramas chopping 25mm off each end and slipping on the 28mm wide CVs. I'm not too sure how to go about creating the new circlip grooves, whether turning with a part-off tool or strapping a die grinder to the toolpost and grinding the groove. Any thoughts?

Mike - Many moons ago I worked in the aircraft industry and I vaguely remember shot-peening shafts to help create a compression layer on the surface to assist resistance to surface cracking. I suspect metallurgy has come a long way since those days and the technique may have been abandoned. Axle suppliers also talk about axles designed to twist like tortion bars (a la VW rear end suspension) so perhaps the shot peening is old hat.

On the subject of torsion bar suspensions, I read that Colin Chapman tried it on a Lotus (the first 72?) and Ronnie Petersen said it was difficult to feel the sensation of braking. The only way he knew the car was decelerating was when the smoke started coming off the front tyres!