[Kenth]

Originally Posted by 65 Lamnas

Did these same 1967 carbs all come with the airhorn-style idle bypass air feature? There was a little screw under the triangle-shape spring steel piece on the bowl stack vent.

The conical head screw under the triangular cover adjusts/adds air to the upper idle airbleeds on 1967 (1967 only units with #´s starting 703xxxx)-69 units.
On 1970 and later units the same screw adjusts/adds air to the upper main circuit air bleeds.
Rochester named the feature "off-idle" adjustment.