In Reply to: Cast iron distributor update posted by Farmer Dan on October 25, 2018 at 11:46:28:
I found this old post in the archives from Don Barkley on the cast iron distributors. He says they were released in 1941. I'm spitballin' here, but I'd assume anything made from aluminum was either changed to steel or cast iron during the war restriction years. Aluminum would be a valuable metal needed for airplane manufacturing and a bit more involved in making than steel and iron. Based on this, it appears the cast iron units would not have been first used on early 9N's.