Blower Drive Service recommends 8.0:1 as the max for 8 lbs of boost. They also recommend a 110 degree lobe separation angle for use with gasoline (114 for use with alcohol).
Check out the first chart to determine the type of driving you will be doing and use their grind number in the left hand column to choose your cam in the second chart....
http://www.blowerdriveservice.com/camspecs.php
http://www.blowerdriveservice.com/bcamspecs.php