New engine issues

Next time you have a valve cover off, there is a 7 digit number cast into the head on top of one of the intake runners.
Get that number, if for no other reason so that you know what you have.

If your heads are any of the “normal” passenger car 318 heads, the chambers would be smaller than 73 cc’s.
If they were more along the lines of what’s typical for 318 heads, like 64cc’s, then your motor would be closer to 10:1cr.

But, that doesn’t really jive with the 120psi....... which is part of the reason for the confusion(well...... at least my confusion).