Originally Posted by
sosidge
Locally we've found that a well sorted gear diff is always faster than a ball diff by a couple of tenths a lap.
Pretty much on the money. We do have a guy running locally who's very fast with a ball diff, but it's very notchy and he's an incredibly good driver. Oil filled diffs, spools and locked up stock diffs are the order of the day for everyone here.
An odd effect of the tighter diffs is that RWD cars have been knocked almost completely out of contention. Once the problem of getting the power down in the FWD cars was sorted, that was it. Also, the M06 is an over-engineered, fragile, turd of a car. (M04 still rocks.)