Mounted an autolite 2150 carburetor on 76 F250 FE360 that incorporates a spacer with PCV connection between the stock 2bbl intake manifold & carburetor.

The throttle plates drag on the spacer holes.

The spacer holes are even slightly in diameter than intake manifold holes .
The autolite 2100/2150 series has Venturi sizes that range from .98 to 1.33".

Do the Autolite 2150 carburetors have different throttle plate sizes which could cause this slight interference issue?

 

the venturi size is not of issue, there are a couple sizes of throttle blades for even a 1.23 carb, at least in the autolite 2100's. Never had a problem with any ford stuff swapping or changing unless on a mr gasket 2bbl adaptor ot 4bbl intake. I would suspect the throttle shaft is sticking or seizing in the aluminum carb bore itself.

 

I have had gaskets with holes too small, I just trimmed the gasket. If it is hitting the spacer, ream the holes out, it likely would not take much.