The Washington times. [volume] (Washington [D.C.]) 1902-1939, 1928-06-20

surveyed asked Tor any gear +
Buyers inquire as to the speed Of
i car. the horsepower Of the motor,
the hlll.climbing ability. but appar-
entity never consider that gear re.
dllction plays vital part in all
these factors. Even gas and oil
economy. AZ well as the life OF the
engine. IS closely interviewer with
the gear ratios.
Quite Complicated
On the motorists side 1t must be
admitted that an effort to gain
knowledge OF the subject is com
pIicated not only because reduction
ratios differ lii different models Of
even the same make and current
chassis model of cars. but also be-
cause the size of wheels materially
AIEers the actual ratios. In addl-
tioTi. there Is q wide variation II
ratios for different speed con1bina-
tions Of the transmission, so that
low gear ii one car may be lower
than lii another, and second speed
may be much closer to high.
some idea OF the in1pertance OF
gear axle ratio. as well as the gear
reduction In the transmission. may
be gained from the fact that an
engine of average horsepower out
put would be capable Of giving
even poor results liz there were no
raffn ~ reduction at the rear axle
II FOR instance the arrangement
were such that the rear axle re-
polped once for every revolution OF.
the engine c1ankshaft, the engine
would stall every time the driver
tried to start the car unless ne
raced the engine and used the
clutch 10 take up the shock q
starting.
Speed and Power
Yae engine, moreover would not
mn the car. The power OUTPUT Of
= = internal combustion engine ls
pfoD0rtional To its speed and Whens
s IA the arrangenleilt theoretically
outlined above, the engine ca mot
develop this speed II conseu tlentiy
cannot develop adequate power.
Thus, IT is customary ~ al
makes Of cars 10 allow the engine
shaft to revolve several times "
every one revolution Uf the rear
wheels. even when q car is supposed
to be IN direct drive.
This constant reduction. regulal .f.
by the aeshing Of the pinion WITH
the ring gear in the rear axle. aver
ages about As 10 That -, Tue
average engine l'eYolyes four anu
One-half times for every revolution
or The rear axle when there -
direct drive through the TRANSMITS.
zion. A number OF cars. especially
since the heavier closed models
have come into vogue. have reduc-
lions ii The neighborhood Of ; e I,
some 90 even higher than TINS,
while there are others winch STOW
less than to 4 In several lines,
roadsfera. which are lishter ana
h,silt more definitely for speed plIF-
poses. have redncticns RI less tnan
High Gear. Low Ratio
~ ,a important to bear In mind.
,fhat s hfrh.xeared car is one IN
Vv1irh the figures Of the ratio are
lower. A car that is geared ; to i.
for instance. Is 3 lower geared car,
although one may be inclined 70
y.isunderstand this and call i A
iigh.geared car simply because the
figures OF the ratio are higher than
cases have been known where
nerwons have purchased cars with
The constant rear axle reduction
ratios unsuited to the needs Of the
country IN which they drive Some
a,.fonobile manufacturers se n q
hfvhSr reared cars to those sections
~ the country where thef pp0grap ply.
= ~ ! level nature, routing the
fnu scared cars TO mountainous
re~iosas. But occasionally owners
,,,,rrhsse machines in sections. OF
fhe country where they do not IN
tend 10 use them regularly. This
.nrnefif1es results In dissatisfied lon !.
The n1otorist who has tonght 2
hfeh-3eared car and who tries 70
,sre II IN mountainous regions finds
that he hasn't got a very good hill
climber. while the owner who has
rreaf stretches Of level where ne
wants to exercise the speedometer
surely will he disappointed IL he has
purchased a IOW-geared car.
Puzzle to Owners
There a considerable variation iIs
the additional gear provided by the
reduction speed In transmission.
SECOND gears usually are less than
10 i. and IN some cases they so
nearly approximate the direct drive
~ third speed as TO he a puzzle 10
csr owners In one typical in
stance q motorist WAS long time
discovering that his second gear
was so high IS to give his car
very little more performance than
In third. This also accounte6 for
the fact that he was able to achieve
relatively high road speeds in sec
ord gear.
Ordinarily, IL second gear Is reas.
onably low the car cannot run in
this gear combination without a
good deal of noise above speeds Of
Is miles an hour. bur it will have.
greater performance on hills in this
gear combination.
Because low gear is very low In
some ears, it has become more eof
IN emergency gear combinations 10.
= .