I am thinking though that the added mass to the lifter assemblies will raise the risk of valve spring failure.
I also think that these considerations are just illustrating the compromises inherent in this type of a design. Overhead cam engines seem to run on forever in comparison.
I mentioned Ford small blocks simply because they share design features along with the Cleveland.
I have seen less rocker arm wear on the tips on the stamped steel rocker arms of the Cleveland than the cast iron tips of the small blocks but the problem is still there, i.e., the scuffing motion across the valve stems.
Remember that when these engines were new they were designed with a packaging level in mind by their manufacturers. This is what you got for the money spent.
Chevys I will point out, have the same valve train issues with mileage for essentially the same reasons.
My opinion of the rocker arms is that the fulcrums of the rockers themselves is a relatively small issue. That irregardless of whether or not it is a ball or another shape is essentially a cheap type of bearing.
The push rod pockets are as well.
The tips are what need to be rollerized.
Roller lifters were not only introduced in production engines as a result of the ZDDT issue but also as a way of reducing parasitic energy losses in a fleet fuel economy battle considering the building of mass quantities of engines. Gaining a few tenths of a mile per gallon because of less friction in the valve train shows some in the fleet averages.
That is a just positive benefit of environmental green government requirements that inadvertently helps performance.
As one engineer pointed out, high efficiency is high performance.
Sometimes the bumbling numbnuts that we elect to government actually do something positive, even if it was accidental and they had no idea they did?
