Milling down SM 68cc CNC heads?

With that little cam I wouldn’t be trying for 10:1 myself(although the 114lsa will help with that to some degree).

An unsolicited critique of the combo.......
A 318 with cnc ported heads and a pretty small cam seems like a combo that’s pointed in two different directions.

We see this more and more lately.
Everyone is throwing there stock heads away when all they needed was a valve job and a truing of the deck, for race heads and then trying to cruise with them.