I have a new set of CP Carrillo pistons with 0.991" pins, fitted by CP at just 0.0005" clearance. That's fine by me.
My rods are steel BBC L88/LS7s that have have all been bronze bushed, and I feel they must have been a sloppy pin-fit with the previous 0.990" pins, as some pin bores are out of round by as much as 0.0005".
They are not tight at the sides of the pin bores to suggest that they have been stretched.
What is the recomended pin/rod clearance?
The old "How To HotRod BBCs" book (which I've found to be a pretty good source of info) suggests 0.0005"-0.0007" (on pg142). I think I remember the shop setting them to 0.0010-0.0012" some years back, but I measured them to be about 5-7 tenths more at this teardown.
Oil will be a 30 weight synthetic.
