Hudson 1947 3/4-TON COMMERCIAL, Руководство пользователя

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HUDSON OWNER’S MANUAL 31
CARBURETOR AND FUEL SYSTEM
FUEL RECOMMENDATIONS
The engine in your Hudson car is designed to give maximum performance and
economy with regular grades of gasoline. One of the most important factors in
getting the most out of the fuels available is correct ignition timing.
Regular grades of gasoline have octane ratings of 72 or higher while Ethyl fuel has
an octane rating of 80 and higher. In the regular brands several grades may be
purchased. The lower grades should be avoided in the present day high compression
engines as they tend to cause "pinging" under normal load conditions, which requires
that the spark be retarded for quieter operation. Retarding the spark naturally affects
the performance of the car as well as economy of operation and, therefore, no saving
in operation is obtained. Also avoid the use of fuels which tend to gum up quickly
as they materially affect the operation of the engine.
Premium grades of fuel, such as Ethyl, which have an octane rating of 80 or higher,
permit the use of a more advanced spark timing without knock or "pinging." This
will result in improved performance and economy. It should be remembered, howev-
er, that these extra advantages cannot be obtained from this type of fuel unless the
spark timing is advanced.
For information on "Ignition Timing" see pages 37 and 39.
FUEL ECONOMY
This subject is probably foremost in the minds of all motorists. We hear
considerable about the results obtained by certain owners which may cause others
to wonder how these claims are substantiated. Unless we understand the conditions
under which these figures were obtained they mean very little to us.
Traffic conditions, the terrain, wind conditions, the driver's characteristics as to
speed, idling at traffic lights and many other factors influence the final results. It
should be understood that the conditions under which maximum results are obtained
by the manufacturer are most ideal. By this we mean the cars are driven under
fixed throttle conditions, they are not interrupted by cross traffic, they are driven
against the wind as well as with the wind and no idling and erratic operation is
permitted.
High speed operation requires the use of more fuel as evidenced by the following
data compiled on a representative group of cars.
At 20 miles per hour good gasoline mileage can be expected. At 40 miles per
hour approximately 24% more fuel is required than at 20 miles per hour. At 50 miles
per hour 43% more fuel is required than at 2'0 miles per hour. At 60 miles per hour 68%
more fuel is required than at 20 miles per hour. At 70 miles per hour the percentage of
increase in fuel rises to the point where 98% more is used than at 20 miles per hour.
From these figures it may be clearly seen that as speed increases, wind resistance
becomes greater and fuel economy decreases proportionately.
In the final analysis it is evident that excessive idling, frequent stopping, quick
acceleration and high speed operation have a marked effect on the gasoline mileage
actually obtained.