Retard the total timing two degrees and you'll cure the problem. I'd change the centrifugal advance setting, but I've been tinkering with distributors for over 45 years and I know how to do it. Telling you how on the forum would be somewhere between difficult and impossible.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!