I have experienced the roller lifter/cam problem that started the “slipping lifter theory”.
In the last couple of years a bunch of roller cams had problems with flaking and the word spread like wildfire among racing engine builders that it was because the the synthetics are too slippery. My builder said to stay with dinosaur
oil to be safe since they hadn’t had any problems with it. But, a bunch of cams flaked with the dinosaur
oil too, mine included (Kendall 20w-50).
Now they’re saying that too little friction is not causing the problem. That regardless of the
oil used, the roller spends a good deal of time slipping and not rolling, especially on the base of the lobe.
Due to its very small size, the needle bearing in the lifter is the highest loaded bearing in our engines. We can safely run the lifters 300-500 miles (1200 laps) with regular oil. We are able to double that with
synthetic. My builder still says to break the rings in on regular oil though.
At the recommendation of the cam companies, builders have been going back to rev kits on some 9000rpm valve trains, to help with the cam trouble.
Using Mobil 1 15W-50 on gas and Royal Purple 21 on alcohol
Scott