the 18 deg is nominal , I found out that my 1929 is happiest at around 15 degrees advanced. runs good smooth strong.

also tweaked my spark gap so it ran smooth as well. my engine was rebuilt and is .040" over and now starts and runs like a champ all day long !!

here is the advance numbers from the cheat sheet I have for the 1929 Delco-Remy 633G Distributor, Chip & JYD can validate since they work on these things
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