High oilpressure causes heat, possibly foaming, puts excessive force on the cam-gear and intermediate shaft.
80psi at hot idle in neutral is way too high. 30-50 psi is about normal, depending on oil and oilpump used.
What oil are you using?
Hope you're not running 20w50 molasses-oil in a rebuild engine.
10w30 should be good enough when engine clearances are correct.
PCV system installed and working properly?
Check for excessive crankcase blowby by temporary removing the pcv hose and watch what comes out.
It's possible the engine is creating more blowby than the pcv system can handle. Then it will pressurize the crankcase a bit and oil-vapour/drops comes out dipstick-tube and possibly front or rear crank seals.