VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 Piston ID & Ring Compatibility?

Evening All,

After tearing down the engine in the truck I am restoring I can't seem to identify these pistons, and need to replace the rings. the pistons are all nominally 3.675" +/- .001 at crown stamped STD and numbered. the oil rings crumbled when I pulled them out of the bores. Thought I would be able to get stock rings or some from Egge or similar, but now I'm not sure. Anyone know where they are from and or ring compatibility?

My 3-4 T gauge has gone missing so I didn't get to measure the bores accurately. The tops of the cylinders have a noticeable relief above the piston travel so I doubt it has been bored over. bottom end had 3 shims under each main, and rods had 2. and condition says it hasn't been decked but babbit looks re-poured and badly relieved with oil ways.

[img]https://drive.google.com/file/d/1yl0FbDHtsNYaJSL5t0lGmOeqvDBzwomN/view?usp=sharing[/img]

I'm no expert on pistons but it looks like those are the original 'skeleton' style pistons with 3/16" thick compression rings and 5/32" thick oil rings. You could try Gary Wallace (http://www.earlychevyparts.com/) for rings that will fit however, my guess is it will be cheaper and easier in the long run to replace the pistons and rings as a set with 'modern' replacements from Egge or similar.

I'm sure others with more experience on this will chime in. I for one had my engine bored and sleeved back to standard and used Egge pistons and rings with no issues.

-Tyler

Thanks for that info TJ I’ll try to research the Carleton pistons. After getting the gunk out I found the bow tie and a few casting numbers. The compression and oil rings are all nominally 5/32”

I would like to avoid replacing it the pistons, as it’s not really in the budget after finding a few surprises like a crack in the head :/