My 1951 216 runs well under 15 lbs on the highway and almost zero at idle. It hasn't really changed in 35,000 miles of driving. The main bearings are new and are adjusted to minimum clearance. I think the cam bearings are quite worn. My 38 oil pressure is off the scale when cold,
over 15 lbs when cruising and not much below 7 at idle. So these old 216s have vitals that vary widely.
As far as adjusting the rods, if you still have the pan off it is a good idea. When they become too loose they can wear out very quickly.
