Help with cam choice for magnum 360 please

Quick Question : what valve spring would/should I use with the regrind cam in question assuming a .480-.512 lift?




http://www.compperformancegroupstor...ore_Code=CC&Screen=PROD&Product_Code=26995-16

They use these with the same/simular lift hyd roller, and they fit the mag heads being that they are beehives.
Whats funny is they are saying a max .500 lift...meanwhile the install at 1.7 and coil bind @ 1.060...so anyhow, .540 lift is about all these will handle while maintaining a .100 from/before coil bind.