I picked up a 273 block with domed Commando pistons. The pistons are stamped L2222N and they are .040 over. I think they might be older TRW replacement pistons which would be forged, but not sure how to tell for sure. The bores look good with no scoring but some of the bores have a pretty good ridge and I was told the engine was smoking.
I'm wondering whether it would make sense to try to reuse the pistons in a different block. I assume I have to remove and inspect them, but I'm not sure what to look for.
- What diameter should the pistons be if they're .040 over?
Stock bore 3.630. .040 over= 3.670
- Does the diameter vary from the top to the bottom, or is the skirt the same diameter as the crown?
Piston diameter is measured .500 in. below the wrist pins on the skirt side.
- What diameter should the wrist pin holes be?
Small block wrist pins are .9842 in. diameter
- How do I tell the difference between forged and cast pistons?
Kinda hard to tell but forged pistons are usually smoother than cast pistons with fewer sharp edges. If you compare the two side by side you can pick out the forged ones.