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Exactly WHY does a Carbureted engine quit when you advance the throttle rapidly on a cold day ?

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Evan

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I have experienced my C-90 quitting when I advanced the throttle from idle on a cold day. This will not happen if the throttle is advanced VERY slowly from about 800-1200 RPM.
I understand on a cold day the air is dense and generally free of water vapor so the mixture is starting out lean.
The engine runs perfectly happy at 800 and at 1200 RPM (once you get there). It's NOT that the equilibrium mixture changes so as to not support combustion, because the engine runs fine at 1200 rpm. The only problem is the transition from 800 to 1200. What EXACTLY about the transition is it that causes the engine to quit ?

When you open the throttle does the increased air flow reach the cylinders before the increased fuel ?

Thoughts ?
 

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