Rule of thumb is advance to be all in by 2500 rpm. The motor likes advance at low end so best throttle response is obtained by very quick advance.
For racing with an unblown deal the way we used to do it was to see how much inital timing the motor would take and not kick back on the starter. Depending on the compression..that was about 22 to 25 degrees. Once determining that, we then went in and put the lightest springs and fastest weights possible in the distributor and limited the distributor advance to 18 degrees. The we set the initial timing at 22 degrees...plus our distributor had 18 degrees in it for a total timing of 40 degrees. Just above idle we would have 40 degrees timing and it would leave hard.
I run mags and no msd but I think the rev limiter deals drop out cylinders to keep the revs contained.