I talked to John this afternoon. He said that the forged pistons pin bosses are too narrow for OEM rods, but that OEM-spec. 312 pistons can be used with the H-beam rods.

I just watched John Mummert's H-beam rod video (again). In the video, it's said that the H-beam rods can be used with either cast or forged 312 pistons. However, the website says that the forged pistons can't be used with stock rods. How can the H-beam rods be used with cast pistons, but the forged pistons can't be used with stock rods?