Roller LA Deck Height

I think at this point, if you want as little over bore as possible, you need to get the 360 block measured out to see how worn it is. A 92 LA 360 probably had a TBI injection system and they often had minimal bore wear.

There are several different piston combinations available off the shelf that will get your desired compression just by moving around the numbers, with a little block decking here, or a little more or less gasket thickness there.

If the bores are straight enough with no ridge at the top, there is a forged Diamond piston available under part number 51400 that is 4.005" bore with a 9cc dish volume. That would land right at about 9.84 to 1 compressor with your 64 cc chamber, pistons .010" down, and a .030" thick 4.03" bore Cometic head gasket.

Diamond 51420 is the same 9cc dish with a 4.02" bore, gets to 9.9 to 1 compression with 4.05" bore Cometic gasket.

I looked at a lot of these pistons when I was shopping for mine, but my block was already .040" over, so I used a 4.04" IC742 piston, and with my 58cc Edelbrock heads I am coming in right at about 11 to 1 compression.