I should have said, blowing oil out the block vent tube.
I also run 6 quarts in the crankcase at track events and the problem only happens thru turn 10 at Summit Point (fast long right hander).
Note "mature block" meaning,
- old
- wore out
- on its last leg
- many thousands of miles
- needs work
- hoping I don’t blow this thing while I’m here (on track)
But hey, running Amsoil 20w50 and it just keeps going and going and going . . .