compression check ?

My motor is a 73 360 thats been checked for cracks, bored 30 over, decked and line honed. I'm using the KB107 pistons and have the edlebrock aluminum 60779 heads. I don't remember the thickness of the head gaskets. When doing a compression check on my engine what should the numbers be? Reason I ask is because I did do a compression check and I got 145psi on cylinders 2,4,6 and 8. Cylinder #1 140 psi, #3 165, #5 150 and #7 150
A buddy said with those numbers its more like a 8.5:1 motor instead of 10.5:1 Any comment on this would be greatly appreciated as I don't understand this stuff.