This intake appears to be a '56 Mercury with a Carter WCFB attached, but I can't decipher the date code on the intake.  5BQ doesn't make sense, but 65B seems to work.  Carb and
intake appear to go together.

I think I figured it out.  I have a couple exhaust manifold with date codes that also start with 5B.  I think they substituted the 'B' for the number '8' since they look similar when rough cast.  Just a theory since I can't find any reference to a different date code pattern.

MattK.  The Carter WCFB you show was only used in '56 on two models only of the Mercs that year.

This carb. with its vacuum controlled secondaries should also have a 'spark control valve' located between the two idle adjusting screws and is a one year only, Mercury only application.  The 'spark control valve' was associated with the FoMoCo Load-0-Matic distributor.  There were two vacuum lines from the carburetor main body that connected to two vacuum diaphragms on the distributor to control the ignition advance curve.  ALL '56 Mercs came with 312 engines from the factory.  Two different series of cylinder heads were used depending upon whether the car was equipped with an automatic or 3 speed standard / 3 speed standard with overdrive transmission.  The automatic transmission cars had a higher compression ratio (smaller combustion chamber) than the standard transmission cars.  My recollection is that the standard transmission '56 Mercs used the 'B' heads and the auto transmission '56 Mercs used the 'C' heads. 

Remember that early '56 production year vehicles will likely have '55 calendar year produced parts.  The '56 model year vehicles came out September-ish me thinks back in the day.

Hope this helps.  


NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

Then the distributor p/n is FDT-12127-B1 that works with the carb.  Can't make out the date code bottom left.  'UA2' or 'JA2'