Misfire at cruise, popping/afterfire at 3000RPM

. 41 is a lot, yes?

Considering the factory spent a lot of time coming up with an advance that would maximize power, how close does 41 at 2800 rpm come to the acceptable range? Even considering the initial timing could be set a couple degrees more advanced if local conditions and fuel permitted.
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Another comparison you can make is to the Direct Connection/ Mopar Performance recommended starting point when using their distributors. With that distributor, 38* at 2800 rpm would generally be OK.
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