I think with the 3.23 gear and 10.5 comp. with alum. heads 224 @ 50 on a 112 centerline would work real well. The highest lift with 1.6 rockers or higher. Remember the alum. heads effectively reduce the comp. ratio. I would try to up the comp. ratio to 11.0 also. Just my 2 cents worth but copper pennies. The old 68 manual cam is a excellent choice always.