Curious (extraneous?) Muncie Casting Numbers Question

[Ronald M.]

I'm in the midst of total frame off on my 66 (yes, I've fallen prey to the mode of 'well, while that's apart I also ought to...')
- so I thought I'd go through my M20 as well - especially given the way I've thoroughly abused it these past 32 years. After cleaning the main case a bit, I noticed these 'Roman' numerals cast into the main case 'II R' and 'X III'. Anything meaningful to be gleaned from them?

[Joe L.]

Re: Curious (extraneous?) Muncie Casting Numbers Question

I'm in the midst of total frame off on my 66 (yes, I've fallen prey to the mode of 'well, while that's apart I also ought to...')
- so I thought I'd go through my M20 as well - especially given the way I've thoroughly abused it these past 32 years. After cleaning the main case a bit, I noticed these 'Roman' numerals cast into the main case 'II R' and 'X III'. Anything meaningful to be gleaned from them?

Ron------


I've wondered about those, myself. I'm sure there is probably an interesting story as to what they mean but I expect it's been "lost in antiquity".

What we need is someone that was involved in the manufacturing process of these cases. I'm not even sure where these were cast. I know of no GM foundry that produced green sand aluminum castings at the time, so I would have to guess that the castings were produced by an outside supplier. I suppose it's possible, though, that these were cast right at the Chevrolet transmission plant in Muncie, IN. I doubt it, but it's possible.

The extension housings, side covers, and rear bearing retainer plate were die castings and these could have been cast at the GM foundry in Bedford, IN or an outside foundry.