What is the difference between an aircleaner for 2 barrel 1957 Ford car and a 4 barrel 57?
Difference is the size of the air intake hole on the side of the air cleaner, larger on the 4bbl than on the 2bbl. I have some pictures if you need them for comparison .
Holley 2 and 4 bbl for 57 have the same neck size to a 2bbl air cleaner will fit on the 4bbl and vise versa. Earlier 2bbl carbs had the small neck size