The sun., 1916-12-31
WHY HORSEPOWER
MAY Be ABANDONED
White Co. With 16 Valve Four
Is First to Drop Much
Abused Term.
ny X. n. JOHNSTON.

WIN the motor car industry stop using
horse power as a standard in rating
automobile engines?
This problem seems to confront the
industry to-day with results more serious
han at any time In the past. owing
partly to the unftuess Of the formula
now in use and partly to the develop
ment Of small. high efficiency engines.
which develop power out OF all proper
tion to the ratings thcy would take.
The White Company. In introducing n
sixteen valve four cylinder motor Of the
high speed type has discontinued horse
power ratings because the word horse
power has become meaningless In its
reference to White cars. az well as In Its
application to other motor car engines.
A close study of the specifications OF
the leading cars in all of the various
power cl~assifcations discloses the fact
that scores OF engines develop power far
In excess OF the ratings which they are
given under the standard formula. In
other words. there Is a big difference be-
tween the rated horsepower and the
actual horsepower. And while the diff
ference II in the buyers favor he sell
dom appreciates that there Is a differ
ence.
ItoW the WI W W ~ ouNau
tage Of some engines and to the disad-
vantage Of others Ia illustrated In the
sixteen valve -four" which the white
Company will show at the Automobile
Salon In the Hotel Astor. This Is an
engine OF comparatively small size and
would ordinarily tax a low rating. yet
II Ii actually one OF h most powerful
engines employed In stock cars. and II
will be sold on the basis OF its power
performance rather than on AZ obsolete
rating.
The reason for this policy lies IN the
method by which all horsepower ratings
are determined. Sine the earliest days
Of the industry engineers of motor car
companies have chung to the original
formula which In based on the bore of
an engine. but which does not adequately
tax into ccOun the length OF the
stroke. In this formula the diameter
COR bore) Is squared. then multiplied
by the number OF cylinders and finally
divided by 2k. which II a constant
based on 1000 feet Of piston travel a
minute.
UGH a formula served its purpose
when all engines were designed with
about the same ratio between the bore
and stroke and when all engines showed
approximately the same number Of
- w AuA NV q
further development In design brought G
wide difference IN dimensions as wei
as in engine speed the engineers tries
To- evolve a new formula which woult
be- more applicable TO the changing de
signs. This new formula, however, ma.
never materialized. even though 1t II
greatly needed. Practically all power
therefore,. Is measured by the old out o.
date formula
II IL thus natural TO expect . BIZ
difference In the performance Of twy
engines hich carry the same rating
IL Ii also confusing to the motor ga
buyer. When an engine Is rated at ~
horsepower and actually develops II
what is the value of such a rating
Or when an engine !s rated at so ans
develops only 80 what doe the ratinI
accomplish"
Horsepower should be valued no
according TO The rating nor the CLAIM
but rather according to the result !
produces. Two engines Of equal horse
power seldom deliver the same drivim
energy at the rear axle, because o
differences In the weights of the car
and bccaus OF power losses between tn
engine and the driving wheels. whel
a 30 horsepower a Of one design vii
deliver exactly the same performance a
a 60 horsepower car Of another desig
II IL apparent that one must be In
efficient and wasteful. with no bala nc
between power available and weight Z
be owe
In the absence OF any formula whic
hts present practice In engine desig
and with the public thoroughly confuse
\ the White Company regards It as
matter Of duty to discard horsepower
and substitute nerfOrmaDce"