3671156 340 standard size pistons
If the number on the piston is actually 3671155, and looks like the number in the first following picture, those are original Chrysler pistons for 1972-1973 340 engines. That is the casting number of the piston. In standard size, the original finished piston part number is 3621252.
These factory pistons are cast aluminum, not forged. They are a flat top pistons with four valve reliefs and a nominal rated compression ratio of 8.5:1. The following picture shows the top of the piston:
The following picture show the other inside markings which include a similar casting number, one digit off, foundry marking, and a Pentastar.
If the number on the piston is actually 3671155, and looks like the number in the first following picture, those are original Chrysler pistons for 1972-1973 340 engines. That is the casting number of the piston. In standard size, the original finished piston part number is 3621252.
These factory pistons are cast aluminum, not forged. They are a flat top pistons with four valve reliefs and a nominal rated compression ratio of 8.5:1. The following picture shows the top of the piston:
The following picture show the other inside markings which include a similar casting number, one digit off, foundry marking, and a Pentastar.