I have a 77 motorhome 440 that has dished .060 over pistons in it. The only numbers i can find on them are 1886 inside of the skirt. I cant find any info on them and was someone might know what they are.
Im not sure what the pistons are but they look like the pistons that belong in the blow through turbo set up that came on some motorhomes.
I have the exhaust manifolds and turbo from one.
Also there were 1.928 pistons factory but I don't know about a 20cc dish