i rday, April 18, 1970
THE MICHIGAN DAILY
irday, April 18, 1970 THE MICHIGAN DAiLY Pog. Nine
You bet we do! General Motors has made a public pledge
to solve the problem of vehicle emissions in the shortest
possible time. We're working in two directions to accom-
plish this objective: finding new ways to further reduce
pollutants from our current engines and exploring, through
aggressive research programs, new low-pollutant power
GM BEGAN EMISSION CONTROL
RESEARCH 20 YEARS AGO
It was some twenty years ago that GM initiated its first
research into the control of vehicle emissions. The imme-
diate problem was air pollution in the Los Angeles basin.
At that time, air chemistry and the reaction of vehicle
emissions in the air was a little-known field. Even today,
scientists are only beginning to unravel this immensely com-
WHERE THE EMISSIONS COME FROM
While it was known that trace amounts of the hydrocarbons
which make up gasoline are not burned in the combustion
process, it was generally thought that these unburned
hy drocarbons were emitted only through the exhaust sys-
tem. GM scientists learned that only 60% of a vehicle's
unburned hydrocarbons were emitted through the exhaust
system-20% escaped through the crankcase vent and
20% through evaporation of gasoline vapors from the
fuel tank and carburetor.
EMISSIONS FROM A CAR WITHOUT CONTROLS
The major emissions from a car without controls are un-
burned hydrocarbons, carbon monoxide and oxides of
nitrogen. Of these, the unburned hydrocarbons were rec-
ognized by GM and government scientists as being the
major contributors to Los Angeles-type smog and were
selected for emphasis in control. As in most technical ad-
vances, progress in controlling these- emissions was made
in a series of steps, not in a single dramatic leap.
CLOSING OFF THE CRANKCASE VENT
The first step was the development of they Positive Crank-
case Ventilation (PCV) system. This system, which was
installed in all cars sold in California beginning with the
1961 model (1963 model, nationwide), substantially elim-
inated the 20% of pollutants being emitted through the
crankcase vent. This was done voluntarily prior to the
existence of government standards.
EXHAUST CONTROL MEASURES
Next, systems were developed to control exhaust emissions.
Exhaust control systems were installed on most 1966 GM
cars produced for sale in California (all 1968 models, nation-
wide). These systems, along with the PCV control which
previously had been made standard equipment, decreased
the emissions of hydrocarbons by about 60% from the
level emitted by an uncontrolled car.
CONTROLLING EVAPORATIVE EMISSIONS
Evaporative emissions from the fuel tank and the carbu-
retor were the last of the three sources to be controlled.
All 1970-model GM cars produced for sale in California
have these controls. Beginning with 1971 models, GM will
include evaporative controls on its production nationwide.
WHERE DOES GM STAND?
Certification tests, required by the State of California prior
to production, showed that GM 1970 model cars, as
equipped for California use, achieved reductions of more
than 80% on hydrocarbon emissions and reductions of
more than 65% on carbon monoxide emissions compared
with 1960 cars without controls.
We think this is good progress toward our goal of a v
tually pollutant-free car. While the goal is now in sight,
the last mile will be the toughest part of the fight.
WHAT GM IS DOING
As we said, we're pursuing two roads toward our objective
of cleaner air: better controls for the present engines and
new power sources.
Our research on the current engine is looking into the
possible modification of engine design, improved control
systems and possibly fuel injection for more precise air-
fuel ratios. This research also shows that the use of unleaded
fuel would make possible advanced emission-control systems.
After the results of this research were discussed individually
with different petroleum companies, a number of these com-
panies announced that they would soon offer an unleaded
gasoline. With the availability of unleaded gasoline, long-
life exhaust catalytic converters, exhaust manifold reactors
and exhaust gas recirculation systems could become tech-
We are also continuing to investigate alternative power
sources aggressively and completely. We are not committed
to the internal combustion engine and are investigating these
power sources with an open mind. Steam, electric, Stirling,
hybrid and gas turbine engines are being vigorously studied
in the largest research program of its type in the world. We
will have no hesitation in using a practical low-pollutant
alternative to the internal combustion engine.
WHAT CAN THE CAR OWNER DO?
Car owners can actively join in the battle for cleaner air.
First, keep your car in efficient operating condition through
proper maintenance. Studies have shown that proper engine
maintenance can substantially lower a vehicle's emissions.
You should do this anyway to keep your operating cots
down and to make sure you are driving a safe car.
Second, GM dealers will soon be offering a low-cost emi-
sion-control system to be installed on 1967 models or
older (1965 or older in California). The system will in-
clude an ignition control device and call for an engine
tune-up to manufacturer's recommendations. Emissions
are reduced up to 50%. The system will be available in
California when certified by the California Air Resources
Board and nationally, as soon as possible thereafter. Have
it installed when it becomes available.
AT GENERAL MOTORS WE HAVE
ACCEPTED THE CHALLENGE
Our society is rightly placing increased emphasis on the
necessity for clean air. At General Motors we have ac-
cepted this challenge. Over the years we have made a
substantial commitment in people, facilities and funds in
order to solve our part of the air pollution problem. We will
continue this effort until this goal is reached.
A GLOSSARY OF POLLUTION TERMS
Hydrocarbons: Compounds of hydrogen and carbon. Gaso
line is made up of many different hydrocarbons. Both evapo
rative losses and exhaust emissions contain a variety of
hydrocarbons. When baked by the sun they react photo-
chemically with other gases to form smog.
Carbon monoxide: A colorless, odorless, tasteless gas result
ing from the combustion of carbon with insufficient air.
Oxides of nitrogen: A natural by-product of combustion.
Lead: An additive used in gasoline to reduce engine spark
knock. A principal fault is that it fouls pollution control
OUR OBJECTIVE: TO ELIMINATE AIR POLLUTION
AS IT CONCERNS GENERAL MOTORS VEHICLES AND PLANTS
COMPLETE CONTROL NEEDS YOUR HELP.
DO YOUR SHARE BY KEEPING YOUR CAR IN GOOD CONDMON.