Hey guys take a look at these.
I read an article in a performance SBC book I have writen by David Vizard that says these are a great addition to add to your block on assembly if NOT using a flat tappet cam. I haven't heard or seen these used before but I guess they limit the amount of oil that drips through those 8 lifter valley oiler holes to reduce windage? I plan on using a roller cam for my 383 build so I am considering adding these or even just brass 1/4 double ended pipe from the local hardware store. Is there any significant benefit from these things and what else can you tell me about their purpose?