[Adger Smith]

I have never experienced any of the out of round problems.
Over the last 30 years I have filled blocks for Circle track, Drag and mud racers as well as boat racers. A few years ago I took a late mod 305 and filled it and bored it to std. 283 for a boat race class. Freshened it once and I think it is still going.
I use a Machine grout and I let it harden at least a month before doing any machine work. I also increase the Piston to wall clearance by at least 40 -50 % . I always test piston growth before deciding on the final cold bore clearance. A water block cylinder moves, a filled block does not and the pistons still grow with the hot oil and combustion heat on them.
Allow for it. On the circle track Applications I only fill to the oil galley holes in the lifter bores. My theory on that is still have water in that part of the cylinder to pull heat out of the oil going through the lifter galleys.
Seems to keep oil temps in check.