Originally Posted by J Gott
You have to modify the heat insulator block when using a carter 2100s. There is a vacuum port at the base of the carb. If you do not make a "channel" in the insulator block, that vacuum port is blocked and you will have drivability issues. There "channels" in the block for the Rochester B but they do not line up for a Carter.

John G

This modification is not necessary if one uses the Carter mounting gasket instead of the Rochester. The Carter gasket is slotted for the vacuum port.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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