Hi, I hope someone can help me out here. I’m in the progress of upgrading the transmission on my EsCos. I have the front diff sorted but am getting confused with the rear. As a 9 inch diff is out of the question I’m going for 7.5 inch one. I intend to fit Quaife ATB diffs but when looking at their catalogue they list 2 flange sizes. I thought the RWD Cosworth’s had the heaviest duty driveshafts so have been looking at a few complete RWD rear ends. Problem is no matter how I measure the flanges on any I have looked at, they do not measure 100mm or 108mm as Quaife state.
Can anyone tell me how the flanges are measured, and if I am correct in my thinking that a RWD Cossie will have heavier driveshasts.

Confused CheeRS