The Key West citizen. [volume] (Key West, Fla.) 1879-current, 1934-01-30

design of compression head and
other features new to passenger
car motors, the "Blue Streak" en-
CINE with which the 1884 "knee-
action" Chevrolet is powered, is
the most powerful and efficient
engine ever to be produced by
Chevrolet. The 1884 model is now
on display at the Meltzer Motor
Company.
Chervolet's 1884 power plant is
not only more powerful, but
smoother, quieter and more eco
nomical than any of its predeces-
sors. With the same bore and
stroke - 3 5-16x4 inches - this
years motor has a maximum out
put of 80 horsepower at $500
revolutions per minute and pro-
duces a torque of $50 foot-pounds
through a speed range from 500
rpm. to 1900 rpm.
One of the most important i'm
provements effected in this re-
markable moor is in the cylinder
head, development work on which
was begun over three years ago
and perfection of which involved
literally upon thousands of gruell-
ing test miles at General Motors
proving ground.
The possibilities of this new
type of head design were discov-
cred three years ago when Chevro-
let engineers were asked to design
a. racertype engine with a very
small piston displacement and
which. would deliver. exceptionally
high power. This naturally de-
manded valves of larger diameter
that could be placed in the avail
able space in the conventional
manner. The design which accom-
hlishcd the desired results paved
tho wav for the 1884 Chevrolet
engine.
General Changes
To explain the general changes
in the cylinder head in a not too
technical manner, it might be said
that Chevrolet engineers succeed
ed in controlling. defamation in the
head by absorbing the heat from
the last gas burned and at the
same time saved power and econ
omy by not absorbing heat from
the gas which is burned first. This
was accomplished by an entirely
different arrangement of valves
and spark plugs-a new angle at
which they function.
In the new engine, the exhaust
valve is located relatively close to
The spark plug in the area of the
first gas burned. The inlet valve
Is located at the opposite side of
The combustion chamber, farthest
from the spark plug, in the area
If the last gas burned. Thus the
entire mixture is conditioned, be-
.ause the heat absorption is con-
rolled.
In addition to this the Chevrolet
,ylinder head has the advantage
IF high volumetric efficiency. it
self a measure of the filling abili-
ty of the engine and it's subse-
Iuent quick-action defamation
when the spark is applied to the
mixture.
The inlet and exhaust ports are
also increased in area to insure
Tree. unrestricted flow to the inlet
1alves and from the exhaust
valves. which is also an important
factor in attaining high efficien-
". The spark plugs are located
high in the combustion chamber,
'ery close to the exhaust valves,
the chamber at an agile
With the. spark gap so placed that
+ lis always surrounded by fresh
explosive mixture at the instant
If ignition. ,s
- auGu New Engine
!, The new Chevrolet engine also
the results of many
ears experience in providing
ample water space around the
'alves and spark plugs in addition
% means for most effective de-
livery and distribution of water.
By an entirely new method of dis
control. the coolest wa
.er in the system is taken into the
cylinder head and directed toward
he exhaust valve seats, normally
he hottest point in the head. This
ontrol is accomplished by means
IF eight small stamped copper
,ozzles pressed into the lower wall