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Old 09-10-2020, 12:31 PM
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edwardc edwardc is offline
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No points: Electronic ignition.

A properly tuned updraft carb should be a little hard to start.

Years ago, I added an oxygen sensor and an air:fuel ratio gauge. Using an adjustable main jet, I have the ratio at cruise rpm set very close to the ideal 14.7:1.
At idle, I set the mixture slightly richer in order to make starting a little easier. In summer, a cold start with full choke always takes two tries. Very predictable. This increases in the fall as temperatures go down.

I did some experimenting, and found that adjusting the idle mix so it started cold on the first try was significantly richer than 14.7:1 and resulted in more fouled looking plugs.
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1977 Pearson P-323 "Dolce Vita"
with rebuilt Atomic-4

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