[tortuga]

They like alot of initial, say 15-18, and limit total to about 32. Assuming you are using an MSD dizz, you can buy larger limit bushings from 4 seconds flat that limit the total amount of mechanical advance so that you can run alot of initial without going too high on total.
By no means an expert but thats what ive learned. I run 18 initial and 32 total with a 600HP 433 stroker with Ford racing z304P heads, BIG juice cam, and 10.7:1 or so compression.