Blu 64 - the original Carter on a 1966 would have been an AVS not an AFB. The AVS were somewhat problamatic. The earlier AFB's used by Chevrolet on the small blocks were virtually "bullet-proof" except in the area of the idle mixture control screw, where "heavy handed" "mechanics" could break the seat by overtightening the idle mixture control screw.

In terms of both value (dollars) and performance, a worn-out genuine original small block AFB is worth 3 to 4 brand new clones. Even the SR Carter's (same number, service date) are worth more than the clones.

Check the numbers on the units you have. I would suggest you will be far more pleased with a working original than with the clone, and for a much longer period of time.

The good numbers are:

3720s for auto transmission vehicle
3721s for manual transmission vehicle

Jon.

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