The Richmond Virginian. (Richmond, Va.) 1910-1920, 1914-04-12
enormous total Of approximately TO-


/ 100000.
| In the same car driven the same
distance, but with q 2.5 to gear rA-
| ito, the engine revolutions will be APP
proximateIy 100000. Therefore, tina
Cadillac with its two-speed axle pro- L
vided it be driven on the 2.5 to gear.
there is a clear saving of approximate
| ly 5000, 900 revolutions in the engine.
| Suppose that the car be driven, say
| 1000 miles per annum--and this Is
perhaps a fair average--it is not un-
reasonable to assume that the 2.5 to
| ] gear can be utilized during about
5000 OF the 1000 tmiles travelled.
This means. as before stated. a clear
saving of 100000 engine revolutions
1t can readily be seen whaA this means
| in the saving in wear on the crank
| shaft bearings. Now let us see what
else 1t means in tho saving of 5000
miles on the IS to l gear ratio.
| 1t means a saving Of 100000 ex-
plosions in each cylinder or total
| Of 10000 in four-cylinder engine. /
1t means a saving of 100000 revolu-
tons Of the cam shaft. 1t means
saving of 100000 openings and clos
| ings of each intake valve and an equal
number Of each exhaust valves. or a
| total of 100000 openings and clos
Iings of each of the intake and exhaust
valves.
| There are four strokes Of each pis-
ton for each of liz explosions and as
| there is saving of 100000 eXplo-
! sions, II means a saving of total of
| "a. 700, 900 piston strokes. In the Ca
dillac the piston stroke is "a inches
or a total piston travel for each eN~
plosion of twenty-threa inches. AS
/ there Is a saving OF 100000 eXplo-
sious il means Il saving of 34,50o,- Il
/ 600 inches of travel for each piston,
I or total Of 13S. 100000 inches of
piston travel for all four This Is a
saving Of 544 miles of travel for each
piston, or z, 1T6 miles of piston travel
saved on all four. 1t means a saving
| 900. 900 revolutions of the electric
/ generator IT means a saving of g.
| 000,0o spakings at the spark plugs
| One could go on indefinitely were
| they to specifically point out every
movement that is saved, as the saving
/ Is effected on every moving part winch
/ has to do with the generating and
engine back to the rear axle. The
transmission of the power. from the
examples given viii suffice to illus I
trate.
| Friction in motor car, no matter
/ how nearly perfect the car may be
! from a mechanical standpoint, is
something which cannot be entirely
eliminated. Friction always consumes
! "a portion Of the power generated by /
the engine. The more scientifically
| the car is designed. the more skill 1
| fully and the more accurately its parts .
are made and fitted, the less Will be
/ the amount Of friction to overcome. /
I The more rapidly piece OF nechan- i
! ism is running In accomplishing
given result the more will be the /
/ friction created. The more slowly IL
! is running and still accomplishing the (
same result, the less will be the fric-
i ton
The wearing OF parts is caused by /
4 friction in the movements Of those I
parts in contact with each other, hence /
lit naturally follows that the fewer
! movements there are. the less Will be /
j the wear, And as the reductions of
movements run into the millions, it /
can readily be rallied what this means
/ in the saving Of wear on those parts. I
/ The saving of wear and tear" how
ever is merely incidental. The prime
advantage OF the two-speed axle lies
! in the fact that with the high d.
rect gear In use. the speed of the car
lis maintained but with 80 per cent
decrease in the speed Of the engine.
For example, In q car with thirty six /
i inch wheels running on the 40 to /
gear ratio at the rate of twenty one I
miles per hour the engine will be run /
j ming approximately TOO revolutions
per minute. Bring the high gear RAJ |
] ito into use and the speed of the car /
/ will be maintained at twenty-one miles
per hour. but the engine speed Is
J reduced TO approximately 4so revolu !
fiens per minute,
This great decrease In engine speed |
I In it's relation TO car speed accom- |
plishea q number of other desirable 1
things Among these is a decrease
+ in gasoline consumption for a given /
mileage This is due to the fact that
with the engine turning over slowly, /
co1npa ratively speaking, given guam t
tlty is utilized TO greater advantage /
land generates more actual power than
with the engine turning over more /
rapidly.
/ Another great advantage is that with
1 this direct drive high gear ratio, I
there Is obtained an extraordinarily /
| luxurious smoothness and steadiness 1
/ in running, together with a marked 4
| aGietness and a comparative freedom /
i from the vibration which TO greater /
/ or less extent is ever present when |
/ travelling at high speed with low
| gear ratio.
/ II can hardly be doubted that the /
| advent of the double direct drive Is !
l. one OF the most important happenings
of recent years In the automobile in
| dustry.