Potential of not having the oil band exposed to the lifter bore feed hole 100 percent of the time. I know the base circle of the cam has a impact as does the lifter oil band location and/or width. If using them, it can have a impact on the Hi-Pressure Pin Oiler (HIPPO) system on Crower roller lifters because the small 0.024" hole that feeds oil to the needle bearings is located within the oil band. That means it is not getting 100 percent oiling thru that hole.
In some instances the lifter must raise quite a distance before oil starts flowing to the needle bearings thru the small hole. I have no specific number but it can equate to quite a few degrees of cam rotation before it does.
Related video:
https://www.youtube.com/watch?v=JoU_hUgq4O0&app=desktop
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/
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Best time 5.13 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE