the roller cam lobe ramps are designed differently,between the two cams, you can run hydraulic roller lifters on only MILD solid roller cams,with low spring load rates (usually under about 235 -240 duration at .050 lift) but verify with your cam manufacturer, before you mis match components and spring rates, most manufacturers have a cover your butt attitude and will suggest you only use parts matched to run together just as they are reluctant to suggest a different manufacturers lifter can be used on their cam or their lifters on a different manufacturers cam,........... you can run solid rollers on almost all billet core hydraulic roller cams (PROVIDED THE CLEARANCES AND SPRING LOAD RATES ARE REASONABLE FOR THE APPLICATION) cast cam cores tend to wear very rapidly under high spring loads, so that's rarely even an option
your clearance issue would make me suggest swapping to a different lifter design rather than milling the block for clearance
a decent BILLET cam core, proper valve train geometry, moderate spring pressures and quality roller lifters will prevent a great deal of cam lobe wear issues
your clearance issue would make me suggest swapping to a different lifter design rather than milling the block for clearance
a decent BILLET cam core, proper valve train geometry, moderate spring pressures and quality roller lifters will prevent a great deal of cam lobe wear issues