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alexiskai · 03-04-2021, 07:06 PM

I believe it's the reverse: the GAV affects the fuel/air mixture except at idle.

Per Tom Endy, the GAV "ports fuel direct to the cap jet, bypassing the comp jet and secondary well." When the car is idling, air is pulled in through a vent near the top of the carb rather than through the main intake. This flow route goes nowhere near the cap jet. Thus, adjusting the GAV shouldn't affect idle *if* the car is truly running solely off the idle jet.

It's actually one of the ways I've been told you should be checking your carb function: idle the car and then turn the GAV. If the character of the sound changes, you're not idling low enough.

03-04-2021, 07:06 PM	#3
alexiskai Senior Member Join Date: Apr 2018 Location: Mebane NC Posts: 2,350	Re: Fuel/air mixture and engine temperature I believe it's the reverse: the GAV affects the fuel/air mixture except at idle. Per Tom Endy, the GAV "ports fuel direct to the cap jet, bypassing the comp jet and secondary well." When the car is idling, air is pulled in through a vent near the top of the carb rather than through the main intake. This flow route goes nowhere near the cap jet. Thus, adjusting the GAV shouldn't affect idle if the car is truly running solely off the idle jet. It's actually one of the ways I've been told you should be checking your carb function: idle the car and then turn the GAV. If the character of the sound changes, you're not idling low enough.