Just curious why some Holley G carbs have smooth air intakes and some have a groove around them? Also, why or what years are the 2 different styles of manifold clamps?
Corey... the all brass Holley G with smooth intake was used in 1914 and the grooved intake version with the steel bowl is used for the 1915-16 models and possibly a year or so after that. THey switched to cast iron in 18 or 19. You can see the progression in different models beginning with all brass and ending with no brass other than the throttle body lever.
I bought the brass bodied smooth intake carb years ago to go on a 14 but on the plate on the top lid with the 3 screws it reads "Holley Pat Dec 22 1914." The cast date on my block is 10-29-13 so I replaced it with a 4 ball Kingston. I used the Holley on another one. I just figured it wasn't correct for an engine with a cast date over a year before it was patented? Of course I built it from parts, it's mostly correct but that 20's steering column looks out of place. Anyhow thanks for the information.
You can find the correct top for that carb if you look around at swap meets. I think the one you need should say "Holley US Pat Applied For". The tops are easy to swap.