Solid roller cam from Bullet (from their recommendation based on what I was looking for) - 110 LSA, 251/257 degrees at 0.050, 0.620 net valve lift WITH 1.5:1 rockers.
LSA's of 110 to 114 are usually best for engines that will see street dutyas well as the occasional foray at the track. A wider lsa improves idle quality by creating more intake manifold vacuum and allowing less reversion. Intake Centerline: refers to the positon at which the cam is installed relative to the crankshaft.
I previously had a solid roller in mine that was 236/242 @ 0.050 on a 110 LSA and made .600 lift at the valves with 1.65's, and it wasn't all that nasty. Being a roller, it didn't have as much overlap - plus it was in a 461 so the extra inches tended to tame it down some.
A tighter LSA such as the 108° is more prone to detonation Not sure why the 66cc head purchase since the 74cc Kaufman heads would give some additional safety. I doubt you want to replace pistons so a head purchase with slightly larger chambers would be a reasonable choice.
I was looking at his L/C2 206/212@.050 110 LSA or L/C3 214/224@.050 108 LSA rollers or "the daily driver" 224/230@.050 on 108LSA I see VooDoo makes a similar roller to their 60902 HFT.
Pontiac "068" cam LSA - 116 Intake Centerline - 113 Valve Overlap - 63 Intake Opens - 31 BTDC Intake Closes - 77 ABDC Exhaust Opens - 90 BBDC Exhaust Closes - 32 ATDC Intake Duration - 288 Exhaust Duration - 302 Valve lift - .406" Here is a further explanation on cam spec by the guy who specs/grinds them: "Re: Cam Duration: Advertised vs. .050