The following recommendations are from Erson Cams. If you have questions, you can reach their tech department at 800-641-7920.
Hydraulic Flat Tappet Camshaft: 110 lbs Seat pressure/250-280 lbs open pressure
Solid Flat Tappet Camshaft: 130 lbs Seat Pressure/300-325 lbs open pressure
Hydraulic Roller Camshaft: 130 lbs Seat Pressure/300- 325 lbs open pressure
Solid Roller Camshaft: (Minimum Safe Pressures)
Up to .600? valve lift: 200-235 lbs Seat Pressure/600 lbs open pressure
Over .600? valve lift: 250-280 lbs Seat pressure /100 lbs pressure for every .100? of valve lift