The Brookings register. [volume] (Brookings, Brookings County, S.D.) 1903-1971, 1915-12-16
1pert Advice For che
Automobile Owner
ries and Replies Covering Matters Of
ortance to the Man Who Runs a Car

has the automatic spark advance &
the type varied by hand?
In such q system the driver is no
required to manipulate a spark lever
and hence he is relieved Of work. TIL,
advancement Of the spark automatical
ly In proportion to engine speed make.
correction for mistakes on the part o.
the operator. Many claim, however
that with no hand control Of the sparl
the maximum efficiency is not obtain
ed at certain speeds, for many driver:
keep the spark advanced all the time
and retard Ii only when the motor be
gins to knock. Those who do not ia
vor the automatic advance claim that
when the motor Is carbonized the
spark must be retarded considerably
otherwise the motor will knock. This
Is not taken into consideration in the
automatic system. 1t also is stated
the mechanical difficulties may come
up and that the system does not take
into account the loads imposed on the
motor.
Is it possible for a car to climb q so
per cent grader
\ gradient of &c per cent, which Is
equal TO an angle OF about thirty de-
grees, Is considered the maximum
grade a car will overcome. On a grade
Of this kind gravity overcomes trac-
ton.
What is the difference between a re-
versible and an reversible steering
gear?
With the reversible type steering
gear 1t is possible to steer front wheels
by applying power direct to them;
whereas, in the irreversible type, it Is
impossible to move the front wheels
without applying power to the steering
wheel. Most heavy pleasure cars are
equipped with irreversible steering
gears, since they often travel over
rough roads at a high rate of speed.
The irreversibility tends to do away
with the back lash In the wheel that
would be felt in a car equipped with
a reversible steering gear under the
same conditions.
Most commercial vehicles, on the
other hand, have a reversible steering
gear. In making deliveries they often
hit the curb at an angle unless driven
very carefully. The reversible type
often prevents the bending Of the steer
Ing knuckle arms.
Are quarter elliptic springs in front
best for easy riding for very light cars,
and are semielIiptio springs on the
rear tho best?
The advantages and disadvantages
Of the various types Of springs depend
upon weight distribution and the de-
sign of the car. One form OF semiel-
Gptic spring may be superior to a GER.
tain form Of elliptic or three-quarter
elliptic. and vice versa. The spring
problem Is solved best IL examples are
given-that Is, take three cars Of given
weight distribution and design and
then the matter may be thrashed out.
However, ~disregarding design. etc.,
many arguments are set forth usually
in unfolding or condemning certain
spring types.
Spring suspension has been a great
problem to motorcar engineers because
the car must Of necessity travel over
rough roads and at slow and high
speeds. If the object Of the springs Is
understood clearly the relative advan-
tages and disadvantages Of the various
forms will be understood more readily
Springs must support certain members
of the car; they must absorb the shock
transmitted to the road wheels.
Springs to be efficient must prevent the
body Of the car from side swaying. In
other words, the springs Of a motorcar
must be strong to support a load and
resilient to make the Car riding easy.
The semielliptic spring is used In the
majority of vehicles in the front and.
In many, also In the rear. This type
reduces sway greatly and yet Is not
hindered in its movement. This type
Is adapted to carry great weight with
out the tendency to permit side sway.
If semielliptic springs are made to be
exceptionally resilient they must be
made long. This adds to the cost and
at the same time increases the tenden.
cy to side sway. One great objection
to the semielliptic spring is that, II
made sturdy to support great weight.
much Of the power of the motor is lost
through the springs. 1t Is quite evil
dent that when the car. strikes an OBJ
ject on the road the power to over.
come the obstacle Is absorbed by the
spring. Stiff, semielliptic springs are
not to be desired when shock absorb
Ing qualities are factors. for when a
car with such springs strikes an OBJ
struction on the road the tendency IL
for the wheels and axles and perhaps
q portion of the car to leave the ground
for an instant.
In the elliptic spring the tendency
to ! d sway is unusually great. This
type Of spring. II made to be as strong
as the semielliptic. will perhaps lose
much Of the resiliency. Average de-
sign shows that the elliptic spring Il
Tar more resilient than the semiellip
tic and better able to absorb road
shock.
In the th~ree-quarter elliptic type the
problem b more q manufacturing prob