I'm seeing your static compression ratio at closer to 10.6:1 and would counsel you that the cam is too short and the squish is too wide.
I don't have the exact specs on that Howard cam, but a swag would put the intake valve closing at about 33 degrees ABDC. Adding 15 to that and plugging 48 into the KB calculator, along with 10.6, 3.48 and 5.7 gives a dynamic compression ratio of 9.42:1. This motor will not run on pump gas in my opinion. Cylinder pressure will exceed the ability of pump gas to prevent detonation. You'll need either less static compression ratio or more cam... or both.... to drop the dynamic compression ratio about 1 full point, down to 8.42:1.