Dual point distributor ID question

67Dart273 said
53 is not unheard of if you are talking complete full advance with both vacuum and centrifugal AT THE CRANK. Don't forget, "the book" specs for dist advance is DISTRIBUTOR degrees, which must be doubled at the crank.

Doh! That didn't occur to me, because I have no way to directly measure distributor timing. That example is exactly what I have, interestingly.