Carb Question

basically the main difference that i can tell from holley's website info is that the 80450 is calibrated more for economy and the 80457 has the( “Next Gen” needle & seat design eliminates the need for external float level adjustment) you can change parts from one to the other. it would appear that the fuel bowls from the 80457 might be better parts from a performance/adjustibilty aspect. the fuel curve on the 80457 metering block may offer a slight advantage. then again it might be exactly the same. they don't really say. i would expect them to be identical and the jets, power valve, and air bleeds to be different between the two. short answer is i don't think there's any appreciable difference btwn the two.

Neither are performance carbs, both meant to be stock style replacements. The 80457 is essentially an 1850 with the Ford auto trans kickdown lever. I would take it and replace the bowls with a pair from a 3310 750 (never cared for the side hung bowl looks) and kit it, replace the secondary spring for a lighter one.

Check for non-replaceable wear, as in are either of the throttle shafts loose or worn. If they are, rebuild the other one.

zookeeper said:

Check for non-replaceable wear, as in are either of the throttle shafts loose or worn. If they are, rebuild the other one.

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Good advice ? That's where they wear out first.