Need help tuning Quickfuel carb

Oldmanmopar said

One other thing you should know is changing air bleeds in the Quick Fuel carb is easier and has more effect than changing the jets.

Determining Power valve should be vacuum at idle divided by two. 12- 15 vacuum 6.5 power valve, 6-8 vacuum 3.5 power valve. under 6 is a 2.5 power valve. I have a box of power valves 6.5. That is what is usually in the quick fuels when new. Never worked out for me. but we usually need a lower number for big cams.

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This was wrong 45 years ago, and it's still wrong now.

Passing along bad information for decades won't make people any better at tuning.

The power valve doesn't affect anything at idle, unless the valve is defective. If you set the power valve open at half of idle vacuum you will have to crutch the tune up to cover the hole in the fuel curve on tip in.

Set the power valve opening a couple of numbers below cruise vacuum. Mark Whitner posted a great video on you tube of power valve opening at idle and proves the long told tale of half idle vacuum dead wrong.