Interesting that it is so thin, imagine it would twist a fair bit!? Gurd's MK1 he beefed up the rear axel by adding a chunky extra anti role bar, you need the rear to slip a bit in corners.
As soon as the rear inside wheel comes off the ground, rear antiroll effect is over. Why do you want the rear to slip in corners? That axle looks very torsionally flexible to me, for a rally car?
Of course but in reality they slip, look at any racing footage, (F1 being a prime example with the HD slow mo stuff) they slip in the corners, I agree you want them to grip as much as possible but when they do slip, you want both axels to slip at the same time surely? (Maybe not the same amount, i would prefer the rear slips more but in most cases the front wheels of an FWD car let go first unless setup properly). Or am I getting all wrong?
As a suggestion, could some tests be devised using a 10T press and a pressure gauge to measure load and deflection of a std unit in various plains? That way you could compare the fabricated unit on completion and add/remove material until you got the results you needed. Additionally, you may need some gurder type jig arrangement to bold it onto while you weld it up. I remember some attempts to make super doper lightweight mini subframes being binned after the welding phase due to distortion.... (this was in the mid 1970's tho, and welding has moved on massively since..)
