Just bought a LSD Siera Diff from another locost builder for my next R1 engined project.
I intend to run 205/50/R15 tyres.
Can anyone give me some advice regarding the number of teeth required on the diff mounted sprocket or a good starting point?
I want a reasonable top end but I do not want unusable wheel spin low down either. Somewhere in between would be good.

Off the top of my head I think I run about 54 teeth on the rear, (51 is stuck in my head too for some reason) a search will find it as its been discussed, I run four different front sprockets (very quick too change, 1 bolt) depending on road use or too suit the circuit where running on.

This thread

I think the one on the diff (it is being posted) has 53 teeth.
It also has been split to make changing easier. I will run with what I am getting for now as it seems pretty close.
Thanks for the info

Martin