I tried my SC10 diff in my B4 today at Bury indoors and I was impressed. I ran the diff as RTR (no oil, just black grease) and the car didn't 'diff out' at all which was a nice suprise and the handling was very close to the ball diff. The only thing that seemed to be effected was the low speed turn in which made the car tend to be a bit keener to clip the apex but I wouldn't say it was anything bad, just different.
I'd say Bury is a medium grip track and I'll also be trying it at York indoor (Polished floor + carpet), Rossendale (Carpet) and a local polished floor track so I should get a good idea of how it performs. I have a feeling the biggest gain will be on the polished floor track but its all to try
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