what I was thinking. benefit of a roller cam is a much more "square" lobe with more lift and .200 duration for a similar advertised/.050 duration. with his original cam, looking at Bullet's master lobe catalog,
Bullet Cams Master List, and matching his 218@.050 duration, they have a moderate lobe, HR269/327 that is 6 degrees shorter advertised (.006 lift), but 11 degrees duration bigger @.2" lift, and .327 lobe lift (.523" valve lift with 1.6 rockers, or .045" more lift than his cam), and have super aggressive lobes all the way up to the HR270/363, which has 15 degrees more duration and .1" more lift than your cam with 1.6 rockers for the same .050 duration....