Probably an oily mess flying everywhere!
At idle oil pressure in a good 16V should be around 25 lbs hot, up to 60/80 cold when the oil is thicker. It would be hard to see oil flow in the valve train since oil flows internally to cam journals but if you clean everything first you will see plenty of oill gathering in the low spots in the head moving toward the various drain holes at the bottom. There must be a better way to check, someone here should chime in who has one please.