Evening star., 1927-10-23

y
\ about to undergo meta
morphosis that will leave it being
pulled by the front pair. That, at
least, is the opinion of many auto
motive engineers who foresee front.
wheel drive as the next radical
change in automobile design.
A subject of engineering study tor
wears, and talked about and tested
in a few cases, front-wheel drive now
seems about TO become an actuality
because the motor car designer IS IN
a dilemma. He wants TO build less
expensive car. a more efficient car,
one that is safer, more comfortable
and graceful. He cannot do it with
rear-wheel drive beyond certain linz
it's: so he is looking to the possi-
biiities offered by turning the engine
around in its frame and using its
power through the front wheels.
The potentialities of front drive
in these vital respects have been in
dicated in racing cars embodying this
principle. Again the speedway has
served as proving ground.
First among the advantages indi-
Gated in this manner is that 'front.'
drive will be less wasteful OF engine
power, making possible the use OF
smaller motors. Smaller motors cost
less to build, because they require
less iron and steel They use less
gasoline and oil, which means that
operation costs arc reduced as well
as construction costs.
Front nt-wheel drive will be less
wasteful of power because it will
be a close-coupled mechanism; using
the engines output at its source.
The transmission. very short pro-
peller shaft and the differential will
be a few inches apart instead of be-
ing stretched out the whole length
of the car. as in the conventional
design. Where power travels so
short distance it has less chance to
get lost. At present transmission
and differential are from three to six
feet apart. Six or seven inches will
suffice in front-wheel drive, accord
ing to engineering authorities.
A small engine and six or seven
inch propeller shaft will mean the
elimination of a great deal of excess
weight. Tire wear will be cor
respondingly less. Here is another
item of reduced expense that is sig
nihcant.
Just how much. smaller the engine
will be when front-wheel drive comes
into its own is matter of specula-
tion. Some idea may be gathered
from the fact that the little straight
eight, 9lT-cubic-in motors used in
racing cars embodying this type of
drive have been highly successful.
The bore of such engines is only
2 lilo inches, and certainly their
performance, allowing for different
conditions, compares most favorably
with passengc9 car motors of much
larger cylinder size and larger
stroke. 1t scarcely is to be expected
that SO tiny an engine will be used
IN passenger cars, but it is not to be
doubted that reductions in size are
possible.
Greater comfort, every motorist
knows. is one OF the goals toward
which the car designer constantly
directs his energies. Front-wheel
drive is declared to hold especially
bright promise in this respect. Com
fort definitely is involved in the ratio
OF sprung to inspiring weight in a
motor car, and present design gives
unsprung weight an uncomfortably
larger margin than is desirable.
For instance, the present rear axle
carries the heavy differential gears,
the axle shafts, the propeller shaft
and the brake mechanism, as we'll as
the wheels and tires, all inspiring
weight. If driving the car were to
be made the function of the front
axle, this weight would be removed.
Then, the rear axle would carry as
unsprung weight only the wheels.
tires and brakes.
This might seem to BE a process
OF making the rear of the car COM
Portable at the expense of the front.
to which these units would be trans
ferred. This is not the case. how
ever. for in the relocation of pro-
peller shaft and differential thew are
certain to be carried on springs.
incidentally. the removal of these
units would permit the achievement
OF one goal toward which the engi-
neer has striven for years: namely.
the lowering of the body. At pres
ent, even in those cars which have
adopted hypoid and worm gearing
Tor this purpose, the propeller shaft
still presents definite limitation in
respect TO reduction of road clear
ance and the achievement of that
low, rakish appearance that is so
desirable.
In front drive, no limitation to
lowering the body remains except
that interposed by the character of
the highway itself.
Safety is one of the most appeal
ing features of front drive, and that
It permits lower body, of course,
is a factor in this safety. Such a
step means lower center of grav-
ity and a reduced center of mass.
which would give the car an ability
to hang to the road and would rep
resent an amazing improvement over
even what already has been done in
this respect.
Front drive automatically knocks
out one of the worst foes of the
motorist-the skid. 1t is inherently
free from this tendency. In addi-
ton. it permits the employment OF
the transmission brake in its fullest
expression, thereby assuring an
equalization of braking force that is
absolute at all times. The value of