Especially Steve O'Hara (hint,hint)

if you guys could,i'd like the general breakdown of the bdc carbs.
by that i mean a list of the various numbers and whether they were single or double pumpers.
i know that bdc 14's are singles and i thought that bdc16's were doubles.
that's the extent of my knowledge.
the reason i'm asking is that i am going thru my pile of mcculloch carbs and rebuilding a few.
i hadn't checked their numbers but i noticed that the fuel inlet was considerably bigger on two so i looked at the numbers and they were bdc16 and bdc22.
so it seems i have several that are stamped bdc16 or 22 that are set up with single pumpers.
is this normal or a distant mod that was done for unknown reasons?
thanx dave
