I agree with 'A Snake' my first concern wouldn't be the pressure but the fact that there may be something preventing
oil getting from the pump to the engine. I got about 35 psi while priming my engine which had similar clearances. I was using a cordless drill that doesn't spin that fast so if you are using a faster higher power drill you may just be pushing a much higher volume of
oil. Try running the drill a little slower and see if the pressure is still at 80 psi. Next take off the hose from the filter back to the engine and run it into an
oil pan while you spin the pump with a drill. If you get good flow then at least you know the oil is getting that far. Beyond that pulling the spark plugs and spinning the engine on the starter to look for oil in the top end around the rockers etc that would have come from the lifters up the pushrods would also give you a little more confidence. Did you use a lot of assembly lube when assembling the engine? Maybe that is making the bearings seem like they have tighter clearances. If it were my engine I would want to know that I had good oil flow to the entire engine before starting it up.