Distributor Curve Resources?

[derf <derf247@gmail.com>]

Anyone have any good reference material on distributor curves for
A-series engines?
Vizard states how important it is but says nothing about how to
achieve a good curve.
I know it is a mostly motor specific thing, but I'm hoping for a ball
park estimate to get me started.  I'll be running a mild street engine
with mild performance cam, ported head, LCB, single SU.
Cheers,
Derf