Do you have the correct flange gasket between the carb and manifold? Some of the rochester flange gaskets do not have the vacuum hole that allows manifold vacuum to the power valve. If this hole in the bottom of the carb is covered, it will open the power valve and your engine will not idle and die as long as the throttle blades are closed.
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Last edited by sstock; 08/23/2019 6:39 PM.
1953 Chevrolet 3100
261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done
In the DITY Gallery
Video of the 261 running

1964 GMC 1000
305 Big Block V6, sm420, the next cab off restoration