Edelbrock springs 1406 and 1405

I posted that pic to show spring strengths and which one for base calibration.
It also says "in absence of a gauge" to go strongest, then work down.
Bewy said
RRR,
I suggest you read post #24 from Edel. Nothing there about 1/2 the idle vac reading. Says to use the strongest spring & if that helps, try a lighter spring. Exactly what I said.
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