# Tri-carb carburetor differences



## 65GTO421HO (Mar 1, 2009)

Does anyone know the physical differences between the '65 and '66 2-bbl Rochester carbs? They have different tag numbers but one person I've talked to said they are physically identical. It doesn't make sense to me that any company would go through the trouble of tagging identical carbs with different numbers if it's not necessary. I suspect there may be jetting differences because the '66 421 has another set of different numbers. The carb p/n's also vary depending on the tranny (auto or manual) so maybe there are different vacuum connects or perhaps it's something to do with the choke. I'm just throwing out thoughts.

Thanks for the help!
Carl.


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