EPA-460/3-73-006a
PASSENGER CAR WEIGHT
TREND ANALYSIS
VOLUME I
EXECUTIVE SUMMARY
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Water Programs
Office of Mobile Source Air Pollution Control
Emission Control Technology Division
Ann Arbor, Michigan 48105
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EPA-460/3-73-006a
PASSENGER CAR WEIGHT
TREND ANALYSIS
VOLUME I
EXECUTIVE SUMMARY
Prepared by
The Environmental Programs Group
The Aerospace Corporation
El Segundo, California 90245
Contract No. 68-01-0417
EPA Project Officer:
F. Peter Hutchins
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Water Programs
Office of Mobile Source Air Pollution Control
Emission Control Technology Division
Ann Arbor, Michigan 48105
January 1974
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This report is issued by the Office of Mobile Source Air Pollution Control,
Office of Air and Water Programs, Environmental Protection Agency, to report
technical data of interest to a limited number of readers. Copies of this
report are available free of charge to Federal employees, current contractors
and grantees, and non-profit organizations - as supplies permit - from the
Air Pollution Technical Information Center, Environmental Protection Agency,
Research Triangle Park, North Carolina 27711, or may be obtained, for a
nominal cost, from the National Technical Information Service, 5285 Port
Royal Road, Springfield, Virginia 22151.
This report was furnished to the U.S. Environmental Protection Agency
by The Aerospace Corporation, El Segundo, California, in fulfillment of
Contract No. 68-01-0417 and has been reviewed and approved for publication
by the Environmental Protection Agency. Approval does not signify that
the contents necessarily reflect the views and policies of the agency.
The material presented in this report may be based on an extrapolation of
the "State-of-the-art." Each assumption must be carefully analyzed by
the reader to assure that it is acceptable for his purpose. Results and
conclusions should be viewed correspondingly. Mention of trade names or
commercial products does not constitute endorsement or recommendation for
use.
Publication No. EPA-460/3-73-006a
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FOREWORD
This report, prepared by The Aerospace Corporation for the
Environmental Protection Agency, Division of Emission Control Technology,
presents the results of an analysis of the historical weight trends of passenger
cars sold in the United States over a 16-year period, 1958 through 1973.
The results of this study are presented in two volumes.
Volume I, Executive Summary, presents a brief, concise review of important
findings and conclusions in the Highlights and Executive Summary sections.
Volume II, Technical Discussion, provides a detailed discussion of each
study topic and is of interest primarily to the technical specialist. In
Volume II, the general analysis technique, parameters examined, and data
sources used are delineated in Section 2. Section 3 presents a graphical
display of study results, together with brief discussions of noted trends. It
illustrates trends for sales distribution, curb weight, inertia test weight
class, wheelbase and length, engine displacement, compression ratio, and
accessory weights. An appendix of tables is included to summarize all
parameters examined in terms of sales-weighted averages. These tables
include breakdowns by market class and by nameplate.
111
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ACKNOWLEDGMENTS
Appreciation is acknowledged for the guidance and assistance
provided by Dr. Karl H. Hellman and Mr. F. Peter Hutchins of the Environ-
mental Protection Agency, Division of Emission Control Technology, who
served as EPA Technical and Contract Project Officers, respectively,
for this study.
Mr. William Smalley was principally responsible for the
acquisition and analysis of the data presented herein. The following
additional personnel of The Aerospace Corporation also made valuable
contributions to the analyses performed under this contract.
L. Forrest
F. G. Ghahremani
D. Smith
N. DeLong
Merrill G. Hinton, Director
Office of Mobile Source Pollution
Approved by:
Toru lura, Associate Group Director Joseph Melj/zer, Group Di^yctor
Environmental Programs jCpVironmental Programs
Group Directorate Group Directorate
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HIGHLIGHTS
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HIGHLIGHTS
vu
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Table 1. Domestic 1973 Models - By Market Class
STANDARD SIZE CLASS
INTERMEDIATE SIZE CLASS
COMPACT SIZE CLASS
SUBCOMPACT SIZE CLASS
SPECIALTY CAR CLASS
AMC (Ambassador)
Buick (LeSabre, Electra, Centurion)
Cadillac (all except Eldorado)
Chevrolet (Caprice, Impala, Biscayne,
Bel Air)
Chrysler (including Imperial)
Dodge (Polara, Monaco)
Ford (LTD, Galaxie, Custom)
Lincoln (all except Mark IV)
Mercury (Monterey, Marquis)
Oldsmobile (Delta, 98)
Plymouth (Fury, Gran Sedan)
Pontiac (Catalina, Bonneville, Grand Ville)
AMC (Matador)
Buick (Century)
Chevrolet (Chevelle)
Dodge (Coronet, Charger)
Ford (Torino)
Mercury (Montego)
Oldsmobile (Cutlass)
Plymouth (Satellite)
Pontiac (Le Mans)
(1.4% of imports are in this class)
AMC (Hornet)
Buick (Apollo)
Chevrolet (Nova)
Dodge (Dart)
Ford (Maverick)
Mercury (Comet)
Oldsmobile (Omega)
Plymouth (Valiant)
Pontiac (Ventura)
(8.2% of imports are in this class)
AMC (Gremlin)
Chevrolet (Vega)
Ford (Pinto)
(90.4% of imports are in this class)
AMC (Javelin)
Buick (Riviera)
Cadillac (Eldorado)
Chevrolet (Camaro, Corvette,
Monte Carlo)
Dodge (Challenger)
Ford (Mustang, Thunderbird)
Lincoln (Mark IV)
Mercury (Cougar)
Oldsmobile (Toronado)
Plymouth (Barracuda)
Pontiac (Firebird, Grand Prix)
Vlll
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HIGHLIGHTS
An analysis was made of the historical weight trends of
passenger cars sold in the United States over a 16-year period, 1958 through
1973. Also examined were ancillary characteristics such as dimensional
trends, displacement and compression ratio trends, and power and luxury
item use trends.
Passenger cars have historically been divided by the industry
into five basic market classes (see Table 1): standard size, intermediate
size, compact size, subcompact size, and specialty cars. These market
classes are closely; but not exclusively, related to wheelbase dimensions.
The specialty class encompasses both large (e.g., Cadillac Eldorado) and
small (e.g., Mustang) high-performance or sports models. Within each
market class there are numerous corporations, domestic and foreign,
producing cars for U.S. sale under various nameplates (Chevrolet Impala and
Ford Galaxie 500 in the standard class, Chevrolet Nova and Plymouth
Valiant in the compact class, Ford Pinto and Volkswagen Beetle in the sub-
compact class, etc.). The number of car models sold in any given year runs in
the hundreds (304 domestic models in 1973). To determine an "average"
weight value for bhe overall market in any given year, it is necessary to
proportionally integrate the sales and weights of each car model or name-
plate sold in that year to arrive at a sales-weighted average weight value.
The weight trend analysis and examination of ancillary
characteristics resulted in the following findings.
A. Sales Trends
1. Total yearly sales of passenger cars in the U.S. have risen from
about 3.15 million in 1947 to 11. 34 million in 1973 . Sale s have
been increasing at an average rate of approximately 315, 000 units
per year over this 26-year period after World War II. Sales in
any given year, however, can vary considerably from the norm
due to general economic conditions, strikes, etc.
IX
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2. Import car sales rose sharply from 1962 to 1970. Although
sales volume continued to rise from 1970 to 1973, their
percent of total sales remained relatively constant (approximately
15%).
3. In 1958, approximately 90% of all U.S. passenger cars were of
the standard size class. From 1958 the share of the market
occupied by the standard size car decreased dramatically,
dropping to approximately 31% in 1973. This was occasioned by
the introduction and public acceptance of the smaller size market
classes during this period.
4. Subcompact sales more than doubled in the 1966-73 period.
Subcompacts, in 1973, were the second-highest-selling market
class (approximately 23% of total sales). The intermediate
class was a close third in 1973, having approximately 20% of
total sales.
5. The four major domestic corporations had 84.5% of the total
U.S. passenger car sales in 1973. Adding Volkswagen,
Datsun, and Toyota to this group accounts for 93.3% of the
total sales. The four domestics plus the top ten imports
account for 98.0% of the total passenger car sales.
6. The percent sales distribution between the domestic cor-
porations has been relatively constant for the last 10 years.
In 1973, General Motors had 44% of total U.S. passenger
car sales; Ford had 24%; Chrysler had 14%; and American
Motors had 3%.
B. Weight Trends
1. Passenger cars in all market classes have shown a marked
and steady increase in curb weight with time. This curb
weight increase trend is independent of manufacturer. For
example, Chevrolet and Ford standard size cars increased
approximately 1100 Ib (33%) and 980 Ib (29%), respectively,
between 1956 and 1974. In the intermediate class, the
Fairlane/Torino series increased curb weight by approximately
1100 Ib (36%) from 1962 to 1974; the Chevelle increased curb
weight 900 Ib (28%) from 1966 to 1974. In the compact class,
from 1962 to 1974 the Chevy II/Nova series increased curb
weight by 940 Ib (36%), while the Valiant increased by 620 Ib
(24%).
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2. The intermediate class car of 1974 weighs about the same
as the standard size car of 1970 (approximately 4200 Ib
curb weight). Similarly, the compact car of 1974 has about
the same curb weight as the intermediate car of 1966 to
1970 (approximately 3300-3600 Ib).
3. The overall sales-weighted curb weights of U.S. passenger
cars dropped sharply from the 1958 level (approximately
3700 Ib) to approximately 3450 Ib in the 1960-64 period.
This was due to the introduction of compacts in I960 and
high sales of both compacts and intermediates in that period.
Since 1964, sales-weighted curb weights have risen steadily,
reaching approximately 3650 Ib in 1973.
4. The overall U.S. sales-weighted inertia test weight average
(including domestic and foreign cars) has the same general
pattern as curb weight variation with time. It dropped
sharply from the 1958 level (3967 Ib) to its lowest value of
3712 Ib in 1961. Since 1961 there has been a steadily
rising sales-weighted inertia test weight trend, reaching a
new high value of 3968 Ib in 1973.
5. Curb and inertia test weight values for domestic passenger
cars surpassed their 1958 levels in 1970 and appear to be on
a still-rising trend. For example, the sales-weighted inertia
test weight average, for domestic cars only, was 4223 Ib in
1973, compared with 4096 Ib in 1958.
C. Dimensional Trends
1. Standard size Fords and Chevrolets have increased wheelbase
approximately 6 in. (5%) and overall length from 1 5 to 22 in.
(7 to 11%) in the period 1957 to 1974. All market classes
show a sharp increase in overall length in 1973 and 1974,
presumably due to safety bumper provisions.
2. Domestic intermediate and compact models also have increased
wheelbase and overall length with time. Some domestic inter-
mediates are now using a shorter wheelbase for the 2-door
model than for the 4-door model. The 1974 intermediates are
as long (206 to 215 in.) as some 1957-70 standard size cars
(200 to 216 in. ). The 1974 compact models (~ 197 in. ) are
as long as 1962-66 intermediates (197 in.).
XI
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D. Displacement and Compression Ratio Trends
1. In 1973, the U.S. total sales-weighted engine displacement
was slightly lower than in 1958. The average displacement
of domestic passenger cars was approximately 20 cu in.
(7%) higher in 1973 than in 1958, even though the sales of
less-than-standard-size cars increased from 10% to 69%
of total sales during this period. The sales-weighted dis-
placement of the standard size class increased nearly 67 cu in.
(22%) to a value of 371.4 cu in. in this same period.
2. The sales-weighted engine displacement of import models
rose approximately 32 cu in. (43%) in the period 1958 to 1973.
3. The 1973 U.S. total sales-weighted compression ratio was
the lowest since 1962 (approximately 8.2). The import
compression ratio rose to 8. 1 5 in 1 973 from 7. 0 in 1958. The
impact of anticipated use of lower octane unleaded gasoline
has been forcing the trend of domestic and U.S. total sales-
weighted compression ratio values.
E. Accessory Equipment Trends
1. Air conditioning was installed on 73% of all domestic cars
in 1973, up from 8% in I960. It accounted for 73 Ib of weight
per car in 1973 on a sales-weighted basis, or approximately
1.85% of the average curb weight in 1973.
2. The other optional power and luxury items are also increasing
in popularity, accounting for 47 Ib per car in 1970, or
approximately 1.25% of the average curb weight in 1970. More
and more of these items (power brakes, power steering,
power windows, radios, bucket seats, etc.) are being made
standard equipment and thus are no longer accounted for as
optional power equipment.
3. Air conditioning plus all other optional power and luxury
items represented approximately 2.9% of the passenger car
curb weight in 1970. This value dropped to 2.6% in 1972
because some items that were optional in 1970 became standard
equipment in 1972.
4. Based on trends from 1966 to 1970, the combined value for
air conditioning plus all other power and luxury items (standard
plus optional) is estimated to be approximately 3.2% of the
curb weight in 1973.
XII
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CONTENTS
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CONTENTS
FOREWORD ....................................... iii
ACKNOWLEDGMENTS ................................ v
HIGHLIGHTS ....................................... vii
EXECUTIVE SUMMARY ................................ 1
1 . Introduction
2. Sales Trends
3. Weight Trends
4. Dimensional Trends
5. Displacement and Compression Ratio Trends
6. Accessory Equipment Trends
Xlll
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TABLE
1. Domestic 1973 Models by Market Class ................. viii
FIGURES
1. U.S. Total Passenger Car Sales ...................... 2
2. Passenger Car Sales by Corporation ................... 2
3. 1972 U.S. Sales by Nameplate ...................... 3
4. Passenger Car Sales by Market Class .................. 4
5. 1973 Sales by Market Class ......................... 5
6. Passenger Car Curb-Weight Trends by Nameplate
(Standard Class) ................................ Ł
7. Overall Passenger Car Curb-Weight Trends (Sales
Weighted) ..................................... 7
8. Curb Weight Trends by Market Class (Sales Weighted) ....... 8
9. Curb Weight Trends by Corporation (Sales Weighted) ........ g
10. Passenger Car Wheelbase Trends (Standard Class) ......... o
11. Passenger Car Overall-Length Trends (Standard Class) ....... 9
12. Passenger Car Wheelbase Trends (Sales Weighted) ......... IQ
13. Passenger Car Overall-Length Trends (Sales Weighted) ...... 10
14. Passenger Car Total-Overhang Trends (Sales Weighted) ...... H
15. Engine Displacement Trends (Sales Weighted) ............. H
16. Engine Compression-Ratio Trends (Sales Weighted) ......... 12
17. Power and Luxury Item Trends ...................... 13
18. Optional Power and Luxury Item Weight Trends
(Sales Weighted) ................................ 14
xiv
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EXECUTIVE
SUMMARY
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EXECUTIVE SUMMARY
! INTRODUCTION
This report presents the results of an analysis of the
historical weight trends of passenger cars sold in the United States over a
16-year period, 1958 through 1973.
Passenger cars are divided by the industry into five basic
market classes: standard size, intermediate size, compact size, sub-
compact size, and specialty cars. The first four classes are segregated
by wheelbase characteristics. The specialty class encompasses both large
(e.g., Cadillac Eldorado) and small (e.g., Mustang) high-performance or
sports models. Within each market class there are numerous corporations,
domestic and foreign, producing cars for U.S. sale under various name-
plates (Chevrolet Impala and Ford Galaxie 500 in the standard class,
Chevrolet Nova and Plymouth Valiant in the compact class, American Motors
Gremlin and the Volkswagen Beetle in the subcompact class, etc.). The
number of car models sold in any given year runs in the hundreds (304
domestic models in 1973). To determine an "average" weight value for the
overall market in any given year, it is necessary to proportionally integrate
the sales and weights of each car model or nameplate sold in that year to
arrive at a sales-weighted average weight value.
The principal topic covered is passenger car weight trends,
but also included is a review of sales trends and ancillary car characteristics
such as dimensional trends, displacement and compression ratio trends,
and accessory equipment trends.
This volume (Volume I) summarizes the more pertinent
information from the analyses. Further details are given in the main body
of the report (Volume II).
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2.
SALES TRENDS
As shown in Figure 1, the total yearly sales of passenger
cars in the U.S. have risen from about 3.15 million in 1947 to 11.34 million
in 1973. Sales have been increasing at an average rate of approximately
315, 000 units per year over this 26-year period after World War II. Sales
in any given year, however, can vary considerably from the norm due to
general economic conditions, strikes, etc. The share of the market
captured by the domestic auto corporations and by all foreign imports is
illustrated in Figure 2 in terms of percent of total sales. Although import
car sales rose sharply from 1962 to 1970, their percent of total sales
remained relatively constant (approximately 15%) from 1970 to 1973.
10
SALES,
MILLIONS
- ft
>U.S. TOTAL
DOMESTIC
O IMPORTS
I
1947 1950 1955 1960 1965 1970 1973
Figure 1. U.S. Total Passenger
Car Sales
GENERAL MOTORS
% SALES 30 -
ALL FOREIGN
AMERICAN MOTORS
1962
1966 1970 1973
Figure 2. Passenger Car Sales
by Corporation
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Figure 3 provides a breakdown of 1972 sales by nameplate.
The larger producers are counted first, and the cumulative U.S. total sales
percentage developed accordingly, as shown. The four domestic corporations
had 85.4% of the total U.S. passenger car sales. Adding Volkswagen, Datsun,
and Toyota to this group accounts for 94.3% of the total sales. The four
domestics plus the top ten imports account for 97.95% of the total 1972 sales.
The percent sales distribution between the domestic corpora-
tions has been relatively constant for the last 10 years. In 1973, General
Motors had 44% of total U.S. passenger car sales, Ford had 24%, Chrysler
had 14%, and American Motors had 3%.
100
80
60
CUMULATIVE
% OF
TOTAL
SALES
40
2,5
2.0
1.5
1.0
0.5
SALES
PER
YEAR IN
MILLIONS
ID a
1 O
u u.
c
>
o
UI
i- <
o
I- o < m i- a
< > o i _i u
:- -i N 2 O *
" O < O O
> 2 w
O
Figure 3. 1972 U.S. Sales by Nameplate
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The distribution of sales by market class during the last 16
years is shown in Figure 4. Most striking is the decline of the standard
size car, which represented approximately 90% of the entire market in
1958. The other market classes have risen proportionally, with the sub-
compact class showing the most significant gains in recent years.
900-
80
70
60
SALES 50
40
30
\
\
'STANDARD
I
I
t
\
v\
COMPACT
INTERMEDIATE
SUBCOMPACT
1958
1962
1966
1970 1973
Figure 4. Passenger Car
Sales by Market
Class
Figure 5 illustrates the cumulative monthly sales variations by
market class for calendar year 1973. As can be noted, the sales distribution
by market class remained relatively constant throughout the year. The
decline in sales of the standard size class was evident at the beginning of
the year; as was the attendant general increase in percentage sales of the
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subcompact, compact, and specialty car classes. The intermediate size
class change from 1972 to 1973 (and throughout 1973) was quite small.
Subcompact sales more than doubled in the 1966-73 period,
and in 1973 were the second highest selling market class (approximately 23%
of total sales). Close behind is the intermediate class (at 20%), whose
sales peaked in 1968 (25% of total sales), but have dropped slightly since
then. Compact car sales peaked in 1962 (25% of total sales), but in 1973
represented only approximately 15% of total sales.
The specialty car class encompasses both large and small
high-performance cars (Cadillac Eldorado, Lincoln Mark IV, Mustang,
Camaro, Monte Carlo, etc.). The increased sales of this class in 1966 are
due to the popularity of the smaller Mustang- and Camaro-type models.
/SOLID SYMBOLS DENOTE PERCENTAGES FOR 1972
40
30
20
10
STANDARD
SUBCOMPACT
-CD D
INTERMEDIATE
3 O
COMPACT
SPECIALTY
FMAMJ JASON
CY 1973
Figure 5. 1973 Sales by Market Class (Cumulative Total
by Month)
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3.
WEIGHT TRENDS
Passenger cars in all market classes have shown a marked
and steady increase in curb weight with time, independent of manufacturer.
This trend is illustrated in Figure 6 for the standard size Chevrolet Impala
and Ford Galaxie 500 (from 1956 to 1962 the values shown are those for the
comparable model offered). Between 1956 and 1974 this increase in curb
weight amounted to approximately 1100 Ib (33%) and 980 Ib (29%) for the
Chevrolet and Ford models, respectively.
4500 i
4000
CURB
WEIGHT,
Ib
3500
3000
GALAXIE 500
1956 1958
1962
1966
1970
1974
Figure 6. Passenger Car Curb-Weight
Trends by Nameplate
' (Standard Class)
In the intermediate class, the Fairlane/Torino series
increased curb weight by approximately 1100 Ib (36%) from 1962 to 1974;
the Chevelle increased curb weight 900 Ib (28%) from 1966 to 1974. In the
compact class, from 1962 to 1974 the Chevy II/Nova series increased curb
weight by 940 Ib (36%), while the Valiant increased by 620 Ib (24%).
For the time period through 1974, the standard, intermediate,
compact, and subcompact size models increased in curb weight approximately
2 to 3% per year on an average basis for the years and models examined.
The major imports (Volkswagen, Datsun, Toyota) leveled off in curb weight
increases in the 1970-72 period; Datsun, however, experienced a 400-lb
(19%) increase from 1972 to 1974.
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The intermediate class car -of 1974 weighs about the same
as the standard size car oŁ 1970 (approximately 4200 Ib curb weight).
Similarly, the compact car of 1974 has about the same curb weight as the
intermediate car of 1966 to 1970 (approximately 3300-3600 Ib).
The overall sales-weighted values of U.S. passenger car
curb and inertia test weights dropped sharply in the 1960-64 period from
1958 values (shown in Figure 7). This was due to the introduction of
domestic compacts in I960 and high sales of both compacts and intermediates
during that period. There has been a steadily rising trend in sales-weighted
weight values from 1962 to 1973. The overall sales-weighted inertia test
weight average in 1973 (3968 Ib) is slightly above the previous 1958 high of
3967 Ib.
Curb and inertia test weight values for domestic passenger
cars surpassed their 1958 levels in 1970 and appear to be on a still-rising
trend. Import cars exhibit a steady rise in curb and inertia test weights
from 1958 to 1973.
4000
3500
3000
CURB
WEIGHT,
Ib
2500
2000
FOREIGN
1500
1958
1962
1966
1970
1973
Figure 7. Overall Passenger Car
Curb-Weight Trends
(Sales Weighted)
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Figure 8 illustrates sales-weighted curb weight trends for the
five passenger car market classes. In general, they parallel the overall
trends of Figure 7. Specialty car class weight trends are clouded because
of the mix of both small and large vehicles. The introduction of new and
popular models (e.g., the Mustang in 1966) can make large variations in
weight for this particular class.
Figure 9 depicts curb weight variations as a function of
domestic corporations and total imports. The sales-weighted average curb
weights of General Motors cars are consistently about 300 Ib higher than
Ford and Chrysler values. This is due to the combined sales of standard-
size cars in a plurality of nameplates (Chevrolet, Pontiac, Oldsmobile,
Buick, Cadillac). On the other hand, the curb weights of American Motors
cars average approximately 500 Ib less than those of Ford and Chrysler.
This is because American Motors cars have been exclusively oriented
toward the smaller-car market until very recently.
4500i
4000 JH
3500
INTERMEDIATE
CURB
WEIGHT, 3000
Ib
4500
4000
3500 -
GENERAL MOTORS
^^
CHRYSLER CORP.
^^
FORD MOTOR CO.
CURB
WEIGHT, 3000
Ib
2500 -
1500
1958
1962
1966
1970
SUBCOMPACT
1973
2500 -
2000 -.
1500
1958
1962
1966
1970
1973
Figure 8. Curb Weight Trends
by Market Class
(Sales Weighted, U.S,
Total)
Figure 9. Curb Weight Trends
by Corporation
(Sales Weighted)
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4.
DIMENSIONAL TRENDS
Standard-size Fords and Chevrolets have increased wheelbase
approximately 6 in. (5%) and overall length from 1 5 to 22 in. (7 to 11%) in the
period 1957 to 1974, as illustrated in Figures 10 and 11. Domestic
intermediates and compact models also have increased wheelbase and over-
all length with time. Some domestic intermediates are now using a shorter
wheelbase for the 2-door model (4 in. less) than for the 4-door model. All
market classes show a sharp increase in overall length in 1973 and 1974,
presumably due to safety bumper provisions.
1974 intermediates are as long overall (206 to 215 in.) as
some 1957-70 standard size cars (200 to 216 in. ). 1974 compact models
(~197 in.) are nearly as long overall as 1962-66 intermediates (197 in.).
122i-
WHEELBASE,
in.
117
116
115
IMPALA
19561958 1962 1966 1970 1974
Figure 10. Passenger Car
Wheelbase Trends
(Standard Class)
225 i-
220
215
OVERALL
LENGTH,
in.
205
200
IMPALA
1956 1958
1962
1966
1970
1974
Figure 11. Passenger Car
Overall-Length
Trends
(Standard Class)
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Figures 12, 13, and 14 illustrate sales-weighted wheelbase,
overall length, and total overhang (overall length minus wheelbase) trends
for the total U.S. passenger car market, domestic cars only, and import
cars only. The total U.S. sales-weighted wheelbase and overall length
values have decreased from 1958 to 1973, despite the fact that all market
classes have increased in these dimensions over bhe same period. This is
the result of changes in market class sales distributions; the standard-size
car was nearly the total market in 1958, but has been steadily decreasing
in percent of total passenger car sales as the other market classes have
made proportional increases in sales. The sharp rise in total overhang
values in 1973 (to exceed 1958 values) may be related to safety bumper
provisions.
DOMESTIC
115
110
WHEELBASE, ,05
in.
100
95
90
19:
^=^-^
U.S. TOTAL^-^ A
-
-
-
IMPORTS
- r . x**3
I I I 1
8 1962 1966 1970 197
210
200
190
OVERALL
LENGTH,
in.
180
170
160 »
1958
DOMESTIC
TOTAL U.S.
IMPORTS
J
1962
1966
1970 1973
Figure 12. Passenger Car
Wheelbase Trends
(Sales Weighted)
Figure 13. Passenger Car Over-
all-Length Trends
(Sales Weighted)
10
-------
85
TOTAL OVERHANG, in.
(overall length - 80
wheelbase)
75
70
65
3401-
320 -
TOTAL U.S.
ENGINE
DISPLACEMENT, 260
ir,3
IMPORTS
I
I
1958 1962 1966 1970 1973
Figure 14. Passenger Car
Total-Overhang
Trends (Sales
Weighted)
DOMESTIC
U.S. TOTAL
IMPORTS
70
1958
1962 1966
1970 1973
Figure 15. Engine Displacement
Trends (Sales Weighted)
5> ENGINE DISPLACEMENT AND COMPRESSION RATIO TRENDS
The trend of sales-weighted engine displacement for
passenger cars is shown in Figure 15 for-the total U.S. market and for the
domestic and import subdivisions. Clearly evident in 1962 is the impact of
large-volume sales of domestic compacts (Falcon, Chevy II, Corvair,
Valiant), which greatly reduced the sales-weighted cubic inch displacement
(CID). From 1962 until 1970, the average CID increased steadily. From
1970 to 1973, the average value of domestic CID declined slightly, but the
import CID continued to rise. In 1973, the U.S. total sales-weighted
engine displacement (CID) was slightly lower than in 1958. The average
displacement of domestically produced passenger cars was approximately
20 cu in. (7%) higher in 1973 than in 1958. The engine displacement of
import models rose approximately 32 cu in. (43%) from 1958 to 1973.
11
-------
Sales-weighted compression ratio trends are shown in Figure
16 for the total U.S. market, for domestic passenger cars, and for imports.
COMPRESSION
RATIO
DOMESTIC
IMPORT
1958 1962 1966
1970 1973
Figure 16. Engine Compression
Ratio Trends (Sales
Weighted)
Following the 1962 reduction in sales-weighted compression
ratio occasioned by high-volume compact car sales, both the domestic and
U.S. total averages rose sharply and then declined to new lows in 1973.
The 1973 compression ratios reflect not only the increase in sales of smaller
car models, but also the decision of the U.S. domestic auto industry to
reduce compression ratio across the board in order to be able to operate with
lower octane unleaded gasoline. Import compression ratios rose sharply and
steadily from 1962 to 1972, but leveled off in the 1970-73 period, again
because of anticipated use of unleaded gasoline. The 1973 U.S. total sales -
weighted compression ratio is the lowest since 1962 (approximately 8.2).
The import compression ratio rose to 8.15 in 1973 from 7. 0 in 1958.
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6. ACCESSORY EQUIPMENT TRENDS
Figure 17 summarizes available data concerning the percent of
passenger cars that have been equipped with various power and luxury items
over the past 16 years.
All items shown have risen sharply in the period 1962 to
1973. Both automatic transmissions and radios were used in over 90%
of all domestically produced passenger cars in the 1970-73 period. The use
of power steering was approaching the 90% level in 1973. Both air condition-
ing and power brakes, at approximately 75% in 1973, exhibit a slope that
indicates that they also may approach the 90% level in 4 to 5 years. The
vinyl top (at about 7 Ib per car) was used in approximately 49% of all
domestic cars in 1973.
100 i
% CARS 50
EQUIPPED
AUTOMATIC
TRANSMISSION
RADIO
POWER
STEERING
POWER
BRAKES
AIR
CONDITIONING
VINYL
TOP
10 -
1958 1962 1966 1970 1973
Figure 17. Power and Luxury Item
Trends (Domestic Only)
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70
60
50
40
WEIGHT,
Ib
30
20
10
POWER AND LUXURY ITEMS
POWER
- BRAKES
DISC BRAKES
STEERING
SEATS
SIDE WINDOWS
TAILGATE WINDOWS
LUXURY
RADIO
VINYL TOP
BUCKET SEATS
CONDITIONING
1958 1962 1966 1970 1973
NOTE: AIR CONDITIONING NOT REPORTED FOR 1958
Figure 18. Optional Power
and Luxury Item
Trends (Sales
Weighted,
Domestic Only)
Figure 18 illustrates the
sales-weighted average weight per car for
optional air conditioning and other combined
power and luxury items over the 1958 to
1973 period.
Air conditioning alone
accounted for an average of 73 Ib per car
in 1973. The sharp drop in average weight
for the combined power and luxury item
curve from 1970 to 1972 is merely a reflec-
tion that a number of power and luxury items
were made standard equipment on many car
models in that period and are, therefore,
not separately accountable as in the past.
Thus, some items previously considered a
luxury are now considered necessary.
At the slope existing between
1966 and 1970 for combined power and
luxury items, their average weight in 1973
would represent approximately 52 Ib per
car, which, when added to the air condi-
tioning weight of 73 Ib, gives a total sales -weighted optional accessory
weight average of 125 Ib per car in 1973.
In 1973, air conditioning represented approximately 1.85%
of the curb weight. Again using the extrapolated 1966 to 1970 characteris-
tics for the other combined power and luxury items, their value in 1973
would be approximately 1. 35% of the curb weight, for an overall total of
approximately 3. 2% of the curb weight (air conditioning plus power and
luxury items).
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