Mark deHaas writes:
> I think that heating pipe in the intake manifold aids in vaporizing
>the air/fuel mixture and also prevents carburetor icing. If anyone has
>driven in a fog or rainy day with the ambient temp. hovering around
>freezing without a "heat riser" that moist air will freeze inside the
>carb until the engine reaches its proper operating temp. Frozen carbs
>are no fun. Especially if you are coming of an exit ramp and the
>throttle is frozen wide open!
Actually, carb ice can occur at *any* temperature. All it takes is
a low spread between temperature and dew point. The carb throat is
a venturi and there is a *significant* temperature drop due to
the pressure change. (That's why carbureted airplanes have a carb. heat.)
-mark
Mark Steph | Live for yourself--there's no one else
exumfs@exu.ericsson.se | More worth living for.
(yes, .se *is* in Texas) | Begging hands and bleeding hearts
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