The Weber 42 DCNF downdraft carburetor. A trio of these on top of the
Maserati C114-1 V6 makes the Citroen SM sing. Carburetors are a fascinating mechanical solution to fluid metering. When they are tuned properly, they are awesome but it only takes one little thing to make you beg for mercy. Keep them clean and tuned for maximum enjoyment :-)
Source: Weber Technical Manual