Give Stefano's mechanic a cigar (was: SPICA airbox nipples

["John Hertzman" <johnhertzman@domain.elided>]

Joe Cantrell wondered about the the nipples on Spica airboxes: "This one has
two nipples on its bottom, one between #1 and #2 intake horns, one behind #4.
They are about 6mm diameter, and lead directly into the outer plenum which
leads directly into the intake tubes.

"Obviously, if there was a negative pressure in the outside plenum,  they
allowed unfiltered air into the engine.  At high speed, ram air might have
overwhelmed the unfiltered intake, but at low speeds, on dusty roads, these
babies would have sucked sand.

"Does anyone know what they might have been connected to?  The front one might
have had a tube to the vapor separator, but I have no idea what the rear one
could have lead to.

"I plan to cap them, but if there's something I've overlooked, please say so.
Maybe there's another 50 hp in here.  Maybe 51.  Or not."

Ian Lomax "always assumed those "nipples" were drain holes.  But then, I have
nothing to back that up..." Dana Loomis replied that he'd "seen a couple of
well-preserved cars that had pieces of green plastic hose attached to those
connnections.  The hoses were maybe 10 in. long and led backward and downward.
I presumed they were for drainage." Stefano's specialist told him they were
just for draining water; Stef had been worried because he didn't want
unfiltered air coming in.

The setup is the same on the 1750, 2000, and Alfettas- same pictures, same
part numbers. The hoses (2300.52063 rear, 2300.52049 front) lead to
105.51.08.200.00, a water drain valve (valvola scarico acqua) which would be a
one-way valve closed to air (and dust-road dust) ingress by the atmospheric
pressure difference.

One more example (or four, if you count people rather than questions) why I
find parts books often more useful even than shop manuals.

Cheers, Cats-

John H.

Raleigh, N.C
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