Evening star., 1934-01-28

which. through the use Of a super
charger that turns at $4,000 revolu-
tions per minute, is raised from q
horsepower peak Of 90 to 1875. The six
cylinder engine in car Of the same
make is made to develop 125 horse
power by use of the supercharger.
Engine Compression
Ratios Increase.
The largest single contribution to
engine output Is that made by the adop-
tion Of higher compression ratios. In
contrast with an average ratio Of So
to last year, this years cars boast Of
an average figure Of 6 to l. One spe-
cial sports model can be had with an
engine head having a 7-to-1 ratio and
numerous others 60 as high as 65 to /.
The figures leave no doubt that the
engine designers have determined to
go the limit in the practice Of squeez-
ing fuel tighter within the combustion
chamber In order to extract a greater
volume of energy out of the same
amount Of gasoline.
Numerous new developments con-
tribute to this now universal practice.
One Of them Is the aluminium alloy
cylinder head. Its adoption makes pos
sible the use of higher compression
without detonation, or knock, by pro.
diffusion. Valves and spark plugs have
been placed in new positions IN the
engine head to provide the engineer
with another means Of resorting to high
compression and its increased efficiency
in fuel use.
Economy Is Improved
Despite Power Boost.
At first glance, such radical increases
in engine output and the adoption OF
higher compression ratios would seem
to refute the vaunted economy Of the
1894 models. That, however, Is not the
case. The new engines are capable OF
burning non-premium fuels without
detonation and the higher compression
ratios assure the extraction OF more
energy from the same amount OF fuel.
Manufacturers are too explicit IN
their claims for improved gasoline
economy to have their word doubted.
They talk specifically in terms OF 20
miles to the gallon at car cruising
speeds Of as high as so miles an hour,
of IL per cent improvement in gasoline
mileage over last year and OF 3 miles
more per gallon than in 1888. They
are speaking on the basis Of exhaustive
checks of actual performance.
II car owners have been dissatlsfed
with engine oil economy during the
past few years. so have the engineers OF
the industry. Moreover, the latter have
decided to do something about 1t. In
spite Of their higher speed, and, conse-
quently, higher operating temperature,
engines this year will be more sparmg
on oil, due to the adoption OF num-
ber of features designed to provide more
adequate cooling for the lubricant.
Other changes in the engine con-
tribute Importantly to their greater
power capacity. Downdraught carpure-
ton not only has become completely
dominant, but also has been improved
in various details to make 1t more EN-
cient and less wasteful OF gasoline.
Manifolding has been modified IN nu.
merous ways to provide for better fuel
distribution between the cylinders.
Ignition Systems Permit
Manual Spark Setting.
More ignition systems have been
modified to incorporate units wh1cn
provide for q supplementary manual
spark advance and retard, which may
be adjusted to compensate for different
grades Of fuel. In other words, II the
motorist desires to change to . gasoline
of greater or lower anti-knock value
than he has been using, . slight change
in spark setting can be made to elimi-
nate any attendant tendency Of the
engine to knock.
Engines are smoother and more silent
in operation than ever. Rubber mount
ings having smothered the major ei-
fects of vibration, engineers have OIL
IN
annoying minor effects with excellent
results. Crankshafts themselves 1ave
been changed, and, in addition, the
number of counterweights increased
Moreover, these balancing units are cast
integral with the shaft In many In
stances, instead Of being bolted on, a.
In the past.
The trend toward making engine con-
troll devices automatic In operation
notably the choke, carburetor idler ad-
iustment and carburetor heat control
has progressed to q point that It in
cludes cars even IN the lowest pr1ce
field.
Higher Charying Rate
Ii Made Automatic.
Another feature Of the engine thai
has gone automatic this year. AND
which is bound to win an enthusiastic
reception from the public, Is the gen
orator Provision is made in the de-
vice now for the flrst time to increase
the charging rate automatically when
the battery is below par or when the
drain upon the electrical system Is ex.
ceptionally heavy. In connection with
the use of batteries of larger capacities
the change Is bound to be appealing
in these days, when numerous auxiliary
lights and electrical devices. including
radio, as we'll as more powerful head
lamps. are general.
With reference to the cooling system
its chief improvement is one designed
to provide for better cooling Of exhaust
valves, which tend to run ut excep-
tionally high temperatures In engines
Of high compression.
The transmission story tlais yer !
(Oontfnned on Twelfth 4a9e.5