First cam cam was regrinded and lifters were used stock, no wonder why two lobes went bad especially when car didnt start for ages.
Second was schneider cam with comp cams lifters and after proper brake in, fifth cylinder started to pop.
I opened valve cover and lash cap was dropped and so was pushrod.
Exhaust lobe were 2mm down.

Like my garage neighbour said: Maybe there are reason why Y-Block enthusiasts are so rare.


Hyvinkää, FI

Ted,
Just curious, but what area exactly are you specifically referring to (cam lobe 'flank'), and why would pitting matter if it's not the part of the lobe that contacts the tappet? (likely, because pitting in general can have negative consequences elsewhere?).
Back when the zinc/cam-failure issue first came up, and people were switching to Rotella, I stocked up before they altered the formula. I still have a couple gallons left, and never worried about the excess detergent since my high-mileage motor was initially neglected by the original owner (a lot of 50s era non-detergent sludge). The bearings are worn enough now that I gain 8# of oil pressure when I let off the throttle, so I always throw in a quart of Lucas with every change, AND since I have another motor waiting in the wings I am not overly concerned about this one, BUT, since it goes against the grain to inflict any avoidable damage to a (still) strong-running (and no doubt internally clean by now) engine, maybe it's time to give away the remaining Roella 15w40 and switch to 20w50?

6 VOLTS/POS. GRD. NW INDIANA

The flanks are those areas of the lobe before and after the nose where the valve is either opening or closing.  While the lobe area taking the highest load hit is the nose of the camshaft, the flanks are still taking a beating and especially where the lash is just taken up and the valve starts to lift off of its seat.  Pitting is just one of the effects seen on those flanks where ‘zinc overloading’ or the opposite where the oil itself is not providing adequate pressure lubrication.
 
Over the course of time, I’ve found three topics that will always bring on a spirited discussion; religion, politics, and engine oil.  Here are my thoughts on engine oil in general.
 
While oil with reduced amounts of zinc/phosphorus (ZDDP) can be compensated for by simply changing the oil more frequently, too much ZDDP creates a situation where the zinc can build up in an excessive layer on the lobe/tappets and in turn can force premature wear in that area when those layers are peeled away when those layers get to high for the metal parts to simply slide over them.
 
Diesel engine oil is higher in detergent than gasoline engine oil and part of that is to combat the excess diesel fuel that gets past the rings on a diesel engine.  If the detergent level is too high, then the detergent can strip the zinc away from the metal parts to which they have adhered and especially if the zinc levels are on the high side where it is layering on the metal to metal contact parts.  Even the reduced amount of detergent in an API service rated oil for a production gasoline car engine is likewise too much in a race engine.   That detergent ends up being detrimental in that the detergent can work its way up past the rings and into the combustion chamber thus making for some unwanted detonation.  Many of the race oils are very low in detergent if they have any at all for this reason and subsequently must be changed out more often. 
 
I was part of a two year episode of engine teardowns performed back in the Seventies where diesel oil versus gasoline oil was used in gasoline engines only.  The diesel rated oil resulted in a measurable increase in both cylinder wall wear and bearing wear when looking at engines with 100K miles on them.  Part of that has to do with the brand of oil while another factor is diesel oil having a lower percentage of base stock oil.  Engine oil technology for the flat tappet engines was at its peak in the late Seventies/early Eighties and with the advent of roller tappet camshafts across the board, the oils have become more application specific.
 
As always, this is just food for thought.  Having worked on engines for almost fifty years now, I’ve torn down a multitude of engines run on the various engine oils which has defined what oils I run in my own engines as well as the engines I build for customers.

Lorena, Texas (South of Waco)