In the late ’70s and throughout 1980s, automakers became very concerned with improving the aerodynamics of their cars for better highway fuel economy and a sleeker, more modern look. What were automotive aerodynamics like BEFORE that time? Actual wind tunnel data for a selection of U.S. and imported 1960 models reveals that some were better than you’d expect — and others (including the 1960 Pontiac pictured above) were much worse than you might think.
Well before the 1980s, there were some scattered attempts to sell automotive aerodynamics, especially where they provided real benefits. For example, the 1961 German Ford Taunus 17M sedan (the P3 “Bathtub” Taunus) had a very decent-for-the-time Cd of 0.395, which gave a higher top speed and better fuel economy for the same engine size — a combination sure to get the attention of German buyers. However, actual data for the aerodynamics of older cars is usually scarce. Automotive stylists were more concerned with looking sleek than being sleek, and even if automakers bothered to measure their cars’ aerodynamic drag, they probably assumed most people wouldn’t understand the numbers and didn’t care.
In 1958, Ford Motor Company established a new wind tunnel for aerodynamic testing. It was a massive new facility, and it was big enough to allow testing of full-size cars rather than just scale models. About a year after the wind tunnel was up and running, Ford decided to measure the lift and drag of 17 1960-model cars, including several imports as well as compact and full-size domestic models from Ford and its rivals.
That data was included in the appendix of a paper Ford engineer Joseph F. White presented to the Society of Automotive Engineers (SAE) in March 1960. An inconvenient snag is that the data did not identify the cars tested by make or model. However, after White’s paper was published, engineer C.J. Heltemes Jr. was able to identify most of the 17 cars, and tabulated their aerodynamic performance based on the Ford graphs. That information was then published in the September 1961 Car Life.
The wind tunnel data measured not only aerodynamic drag, but also aerodynamic lift, which is not so often discussed, but a rather important point. If air pressure over the top of a car is lower than pressure underneath, the car body will start to act like a wing, lifting the car off its wheels! Unless you’re driving one of Nick Fury’s jet cars from the old Nick Fury, Agent of S.H.I.E.L.D. comic book, this is bad news — if you want to be able to steer and stop, it really helps if the wheels are actually touching the ground — and extreme aerodynamic lift can be very dangerous at high speeds.
Ford tested each of the 1960 cars up to simulated speeds of around 100 mph, measuring drag and lift at various speeds. Heltemes only tabulated the data at 80 mph. As I’m sure some one will point out, several of the cars tested were not actually capable of reaching 80 mph under their own power. However, a table of numbers is easier to read than 17 separate graphs, and we work with what we’ve got.
| Model | Body Style | Wheelbase, in. | Frontal Area, sq. ft. | Calculated Cd | Air drag, 80 mph, lb | Total lift, 80 mph, lb |
|---|---|---|---|---|---|---|
| 1960 Ford Anglia | 2-door sedan | 90.5 | 18.0 | 0.52 | 149 | 122 |
| 1960 Renault Dauphine | 4-door sedan | 89.4 | 18.2 | 0.45 | 130 | 121 |
| 1960 Volkswagen | 2-door sedan | 94.5 | 19.6 | 0.52 | 162 | 170 |
| 1960 Chevrolet Corvair | 4-door sedan | 108.0 | 19.7 | 0.43 | 135 | 142 |
| 1960 Ford Falcon | 4-door sedan | 109.5 | 21.3 | 0.54 | 185 | 210 |
| 1960 Valiant | 4-door sedan | 106.5 | 21.2 | 0.50 | 170 | 205 |
| 1960 Rambler American | 2-door sedan | 100.0 | 22.6 | 0.50 | 180 | 190 |
| 1960 Plymouth Fury | 4-door hardtop | 118.0 | 24.4 | 0.48 | 188 | 249 |
| 1960 Dodge | 4-door hardtop | 122.0 | 24.6 | 0.48 | 190 | 218 |
| 1960 Ford Galaxie | 4-door hardtop | 119.0 | 24.9 | 0.55 | 218 | 280 |
| 1960 Chevrolet | 4-door sedan | 119.0 | 24.5 | 0.50 | 195 | 233 |
| 1960 Pontiac | 4-door hardtop | 124.0 | 24.7 | 0.54 | 215 | 216 |
| 1960 Oldsmobile Ninety-Eight | 4-door hardtop | 126.3 | 25.2 | 0.47 | 189 | 225 |
| 1960 Buick | 4-door hardtop | 126.3 | 24.7 | 0.50 | 197 | 215 |
| 1960 Cadillac | 4-door hardtop | 130.0 | 24.4 | 0.49 | 193 | 258 |
Below is a car-by-car rundown. Although the original data included only wheelbase, test weight, and frontal area for each car, I’ve added other specifications so you can get a sense of these cars’ respective sizes.
Imported Compacts
1960 Ford Anglia 105E
Major Dimensions: 153.5 inches long on a 90.5-inch wheelbase, 46.0/45.8-inch track, 57.34 inches wide, 54.93 inches high
Test weight: 2,150 lb
Frontal area: 18.0 square feet
Calculated Cd: 0.52
Aerodynamic drag at 80 mph: 149 lb
Total aerodynamic lift at 80 mph: 122 lb
The English Ford Anglia 105E had debuted in the UK in 1959 and arrived in the U.S. for 1960. It was a very small car by American standards, and just 57.34 inches wide, which contributed to its small frontal area. That partly made up for its mediocre drag coefficient — I think the distinctive “Z-line” reverse-slant roof probably didn’t help the Anglia in the wind tunnel. However, the roofline MIGHT have contributed to the 105E’s reassuringly low high-speed lift.
1960 Renault Dauphine
Major Dimensions: 155.5 inches long on an 89.4-inch wheelbase, 49.2/48.0-inch track, 59.8 inches wide, 56.7 inches high
Test weight: 2,296 lb
Frontal area: 18.2 square feet
Calculated Cd: 0.45
Aerodynamic drag at 80 mph: 130 lb
Total aerodynamic lift at 80 mph: 121 lb
The rear-engine Dauphine looked rather toy-like, but it had the most impressive aerodynamic performance of the bunch. It didn’t have the lowest Cd, but its small frontal area helped to make it quite slippery for the time. Just as importantly, it had the lowest total lift of any of the cars tested.
(Yes, the yellow LHD car pictured here has “Alfa Romeo” badges. This is an Italian-market version, built by Alfa Romeo under license from June 1959. It has a few minor exterior differences from the French car, but the body is the same.)
1960 Volkswagen Sedan
Major Dimensions: 160.6 inches long on a 94.5-inch wheelbase, 51.4/50.7-inch track, 59.1 inches wide, 60.6 inches high
Test weight: 2,246 lb
Frontal area: 19.6 square feet
Calculated Cd: 0.52
Aerodynamic drag at 80 mph: 162 lb
Total aerodynamic lift at 80 mph: 170 lb
The Volkswagen sedan — not yet officially called a “Beetle,” as I’m sure someone will remind me if I don’t point it out — was designed in the 1930s, and its aerodynamics would have been quite good back then. For 1960, they could have been worse. The Type 1 body suffered a lot of rear-end lift, which was much worse than the Dauphine even at 50–60 mph.
Domestic Compacts
Before getting into the domestic compacts, I should note that in March 1960, at the same SAE event where White presented his wind tunnel testing paper, Road & Track publisher John R. Bond presented a different paper discussing the engineering highlights of 25 compact cars, which included his estimates of their aerodynamic performance. I see those numbers pop up from time to time, so I’ll present Bond’s calculations here as well.
(I don’t think Bond’s figures were nearly as accurate as ones Heltemes calculated based on the Ford tests. Bond’s numbers were not based on wind tunnel testing, but on coast-down measurements — letting drag slow the car from a given speed and then trying to estimate how much of the drag was aerodynamic and how much due to tire and drivetrain friction. For some reason, Bond’s frontal area estimates were all higher than Ford measured, which would obviously affect the calculation of drag coefficients, and he also “corrected” his calculated Cd figures in a way he didn’t explain.)
1960 Chevrolet Corvair Sedan
Major Dimensions: 180.0 inches long on a 108.0-inch wheelbase, 54.0/54.0-inch track, 66.9 inches wide, 52.4 inches high (51.3 inches laden)
Test weight: 3,030 lb
Frontal area: 19.7 square feet
Calculated Cd: 0.43
Aerodynamic drag at 80 mph: 135 lb
Total aerodynamic lift at 80 mph: 142 lb
The Corvair sedan fared very well in the wind tunnel, the best of the U.S.-made test cars. Its width gave it more frontal area than the imports, but an excellent drag coefficient made it almost as sleek as the Dauphine. Lift wasn’t bad, although the Corvair tended to raise its nose at higher speeds.
Bond calculated a frontal area of 19.2 square feet and a Cd of 0.435 for the Corvair, which he corrected to 0.42.
1960 Ford Falcon Fordor Sedan
Major Dimensions: 181.2 inches long on a 109.5-inch wheelbase, 55.0/54.5-inch track, 67.0 inches wide, 56.4 inches high (54.5 inches laden)
Test weight: 3,143 lb
Frontal area: 21.3 square feet
Calculated Cd: 0.54
Aerodynamic drag at 80 mph: 185 lb
Total aerodynamic lift at 80 mph: 210 lb
The original Ford Falcon was impressively efficient in weight, but not in aerodynamics. Its 144-cid (2,365 cc) six had enough power to exceed 80 mph even with the dreadful two-speed Fordomatic, but it needed to generate almost 37 percent more power to push through aerodynamic drag at that speed than did the slippery Corvair. (No wonder Falcon owners complained that gas mileage dropped off over 60 mph!) High-speed lift was also concerningly high. Unlike the Corvair, the Falcon stayed mostly level until velocities beyond its actual top speed, but total lift was 48 percent greater.
Bond calculated a frontal area of 20.75 square feet and a Cd of 0.452 for the Falcon, which he corrected to 0.44 — MUCH lower than Ford’s own wind tunnel tests indicated.
1960 Valiant Four-Door Sedan
Major Dimensions: 184.0 inches long on a 106.5-inch wheelbase, 56.0/55.5-inch track, 70.4 inches wide, 55.6 inches high (53.3 inches laden)
Test weight: 3,415 lb
Frontal area: 21.2 square feet
Calculated Cd: 0.50
Aerodynamic drag at 80 mph: 170 lb
Total aerodynamic lift at 80 mph: 205 lb
One of the defenses sometimes offered of the 1960–1962 Valiant is that its oddball styling was somehow good for aerodynamics. The wind tunnel data suggests that this shape wasn’t any kinder to the air than it was to the eye. The Valiant sedan was a little slicker than the boxy Falcon, but its wind tunnel performance was nothing to brag about, and it started to get awfully light, especially in front, if you exceeded 75 mph.
Bond calculated a frontal area of 22.0 square feet and a Cd of 0.417 for the Valiant, which he corrected to 0.41 — also dramatically better than the wind tunnel tests revealed.
1960 Rambler American Two-Door Sedan
Major Dimensions: 178.3 inches long on a 100.0-inch wheelbase, 54.6/55.0-inch track, 73.0 inches wide, 57.3 inches high
Test weight: 3,164 lb
Frontal area: 22.6 square feet*
Calculated Cd: 0.50
Aerodynamic drag at 80 mph: 180 lb
Total aerodynamic lift at 80 mph: 190 lb
* Heltemes lists 22.6 square feet, but the Ford paper says 22.2 sq. ft.
Given that it was a makeover of an early ’50s design, the Rambler American was far from terrible aerodynamically. Its total drag area suffered from its being wider overall than the other compacts, but the American had less aerodynamic lift than the newer Valiant or Falcon, and the lift was distributed surprisingly evenly front and rear.
Bond calculated a frontal area of 22.6 square feet and a Cd of 0.446 for the Rambler American, which he corrected to 0.46.
Domestic Full-Size Cars
1960 Plymouth Fury Four-Door Hardtop
Major Dimensions: 209.4 inches long on a 118.0-inch wheelbase, 60.9/59.7-inch track, 78.6 inches wide, 56.7 inches high (54.6 inches laden)
Test weight: 4,424 lb
Frontal area: 24.4 square feet
Calculated Cd: 0.48
Aerodynamic drag at 80 mph: 188 lb
Total aerodynamic lift at 80 mph: 249 lb
The full-size Plymouth had the lowest drag of the full-size cars — only slightly more than the significantly smaller Falcon — but oh, that high-speed lift! Not only was the aerodynamic lift pretty bad overall (third worst of the tested cars), it was most pronounced in front. At 80 mph, there was about 150 lb of front lift, rising to more than 200 lb above 90 mph. With the optional 330 hp SonoRamic Commando engine, a Fury probably capable of upwards of 110 mph, but the shape of the lift curves made that seem foolhardy, even before considering the problem of brakes.
1960 Dodge Four-Door Hardtop
Major Dimensions: 212.6 inches long on a 122.0-inch wheelbase, 61.0/60.0-inch track, 81.5 inches wide, 56.7 inches high (54.6 inches laden)
Test weight: 4,626 lb
Frontal area: 24.6 square feet
Calculated Cd: 0.48
Aerodynamic drag at 80 mph: 190 lb
Total aerodynamic lift at 80 mph: 218 lb
There’s not enough information to determine if the full-size Dodge Ford tested was a Polara or Matador — it was a big Dodge four-door hardtop, but Dodge offered that body style in both Polara and Matador trim for 1960. Its drag was about the same as the smaller full-size Plymouth. Its total lift was less than the Fury, but I’m not sure that was an improvement because the Dodge actually had an even greater proportion of front-end lift. (How fortunate that Detroit was so insistent on making most of its cars nose-heavy unless very heavily laden.)
1960 Ford Galaxie Town Victoria
Major Dimensions: 213.7 inches long on a 119.0-inch wheelbase, 61.0/60.0-inch track, 78.0 inches wide, 58.4 inches high (55.0 inches laden)
Test weight: 4,552 lb
Frontal area: 24.9 square feet
Calculated Cd: 0.55
Aerodynamic drag at 80 mph: 218 lb
Total aerodynamic lift at 80 mph: 280 lb
A comparison like this inevitably has a loser, and when it came to aerodynamics, the full-size Ford took the booby prize, with the worst drag AND the worst lift. The Galaxie four-door hardtop had more total lift at 60 mph than the Corvair had at 80. Its front-end lift wasn’t as pronounced as in the Plymouth or Dodge, but that was small consolation when total lift exceeded 400 lb even below 100 mph.
There was an additional car in the Ford test data that Heltemes didn’t include, maybe because he couldn’t positively identify it: It was another four-door hardtop on a 126-inch wheelbase, a frontal area of 25.8 square feet, and a test weight of 5,069 lb. Based on that, I think it might have been a 1960 Mercury Park Lane. Its total drag was less than the Galaxie (around 200 lb at 80 mph) and it had less lift (around 250 lb at 80 mph), although was still a lot.
1960 Chevrolet Four-Door Sedan
Major Dimensions: 210.8 inches long on a 119.0-inch wheelbase, 60.3/59.3-inch track, 80.8 inches wide, 58.1 inches high (56.0 inches laden)
Test weight: 4,337 lb
Frontal area: 24.5 square feet
Calculated Cd: 0.50
Aerodynamic drag at 80 mph: 195 lb
Total aerodynamic lift at 80 mph: 233 lb
It appears that Ford may actually have tested two 1960 Chevrolet full-size cars, one a four-door sedan, the other a four-door hardtop (“sport sedan,” as Chevrolet called it). Heltemes only tabulated the data for the sedan. Its aerodynamic performance was average, which is to say “mediocre.”
The four-door hardtop had about the same drag as the sedan. Its TOTAL lift was less than the sedan’s, but its front lift was significantly more pronounced.
1960 Pontiac Star Chief or Bonneville Vista
Major Dimensions: 220.7 inches long on a 124.0-inch wheelbase, 64.0/64.0-inch track, 80.7 inches wide, 56.4 inches high (54.8 inches laden)
Test weight: 5,141 lb
Frontal area: 24.7 square feet
Calculated Cd: 0.54
Aerodynamic drag at 80 mph: 215 lb
Total aerodynamic lift at 80 mph: 216 lb
As with the Dodge, there was no indication of trim series, but the tested full-size Pontiac was a four-door Vista hardtop on the longer 124-inch wheelbase, so it was either a Star Chief or a Bonneville. Its total drag was almost as bad as the Galaxie, and its aerodynamic lift was quite dire. While its total lift wasn’t bad among the full-size cars, almost all of that lift was in front — judging by the graph, it lifted around 180 lb off the front wheels at 80 mph, rising to around 280 lb by 100 mph.
1960 Oldsmobile Ninety-Eight Holiday Sport Sedan
Major Dimensions: 220.6 inches long on a 126.3-inch wheelbase, 61.0/61.0-inch track, 80.6 inches wide, 58.3 inches high (54.2 inches laden)
Test weight: 5,297 lb
Frontal area: 25.2 square feet
Calculated Cd: 0.47
Aerodynamic drag at 80 mph: 189 lb
Total aerodynamic lift at 80 mph: 225 lb
The big Olds unexpectedly boasted the lowest Cd of the full-size cars and the third lowest in the test group. Unfortunately, it also suffered a lot of aerodynamic lift. The main consolation was that the front-end lift wasn’t quite as alarming as on the Pontiac.
1960 Buick Electra 225 4-Door Hardtop
Major Dimensions: 220.6 inches long* on a 126.3-inch wheelbase, 62.2/60.0-inch track, 80.0 inches wide, 57.5 inches high (55.6 inches laden)
Test weight: 5,210 lb
Frontal area: 24.7 square feet
Calculated Cd: 0.50
Aerodynamic drag at 80 mph: 197 lb
Total aerodynamic lift at 80 mph: 215 lb
* 225.9 inches if it was an Electra 225
The Buick that Ford tested was a four-door hardtop on the longer 126.3-inch wheelbase, but there’s no way to tell if it was a standard Electra or the longer Electra 225. Either way, you wouldn’t necessarily think to look at it that the Buick was sleeker than the Pontiac, but it was. Unfortunately, its high proportion of front-end lift was similarly bad.
1960 Cadillac Four-Door Hardtop
Major Dimensions: 225 inches long on a 130.0-inch wheelbase, 61.0/61.0-inch track, 79.9 inches wide, 56.2 inches high (54.3 inches laden)
Test weight: 5,694 lb
Frontal area: 24.4 square feet
Calculated Cd: 0.49
Aerodynamic drag at 80 mph: 193 lb
Total aerodynamic lift at 80 mph: 258 lb
Cadillac offered five different four-door hardtops in 1960, so I have no idea which one Ford tested. Its drag coefficient was surprisingly good; its high-speed lift was the second worst of the group. Total lift crossed the 200 lb mark at around 70 mph and topped 400 lb just past 100 mph, with about two-thirds of that in front.
Summing Up
Considered strictly in terms of drag coefficient, most of these cars weren’t as bad as I would have expected. They weren’t GREAT, but some late ’70s and early ’80s cars were worse. Even some of the newer cars that were trumpeted as being more aerodynamic didn’t do a lot better — the 1979 Ford Mustang, supposedly designed in the wind tunnel with European influence, only managed a Cd of 0.46 in notchback form, worse than a 19-year-old Corvair sedan!
However, the older cars had lots of frontal area, and what matters most in reducing drag is total drag area (which is Cd times frontal area) — a really big vehicle has to be much slicker to make up for the sizable wall of air it’s pushing. Downsizing sometimes helped here, even if the drag coefficients still weren’t very good.
I would be interested to see comparisons of different body styles. For instance, Ford developed the sleeker Galaxie Starliner body pictured above to improve the aerodynamics of the big Galaxie for NASCAR competition, but how much did it actually reduce the terrible drag of the four-door Galaxie Town Victoria? Unfortunately, so far as I know, Ford didn’t release any hard data on that.
Racing aside, you can tell from this test data that aerodynamics were just not a consideration for most full-size cars back then. From a standpoint of performance and economy, it’s easy to understand why: With 200+ horsepower, the 40 or 45 hp that air drag consumes at moderately illegal freeway speeds is less important than it is for a smaller car with an engine displacement of less than 1.5 liters. Drag was a bigger deal for the domestic compacts than it was for the full-size cars, but even there, it was often neglected. (The early Falcon would likely have gotten better highway gas mileage if its aerodynamics were better.)
However, the high-speed lift characteristics of many of these cars were truly alarming, and you didn’t have to be running flat out to feel the effects. The tendency of some of these big cars to turn up their noses started to show up even at 70 mph. For as much as Detroit loved to promote horsepower and performance, they seemed to have great faith in buyers scrupulously observing the posted speed limits.
Related Reading
An Illustrated History Of Automotive Aerodynamics – Part 1 (1899 – 1939) (by Paul N)
An Illustrated History Of Automotive Aerodynamics: Part 2 (1940 – 1959) (by Paul N)
An Illustrated History Of Automotive Aerodynamics: Part 3 (1960 – 2012) (by Paul N)
Automotive Aerodynamics: Drag Area – Size Matters (by Mike Butts)
Vintage R&T Tech Article: “Aerodynamic Drag” (1966) (by Paul N)
I suspect the wheelbase figures for the Corvair and Falcon have been swapped with their respective lengths in the table, either that or they are much longer than they look ^^
Great semi-1st hand info that I had a hard time finding in the process of documenting energy consumption models for older bodyshells, thanks a lot as always.
Oops, yes, the table got a bit garbled somehow. It should be fixed now.
ok, but they sure are pretty, not like the generic jelly beans on the road today. can’t even tell what model or even the year. give me a plymouth fury or a dodge polara with them big old cats eye taillights. I’ll pay for the gas.
Fully agree! While out driving, my wife will say “what kind of car is that?”, because I ALWAYS knew what it was. Now…..I have to see if I can read the name or model, otherwise, no clue.
Also fully agree.
This is interesting stuff. The relatively poor showing of the VW is news to me. And while I would have expected the Corvair to have a better cd than the Falcon, I was surprised by the margin.
Regarding the VW Beetle: it’s been tested many times and the general consensus is that the early Beetles had a Cd of 0.48 and the later ones (1968 up) in the range of 0.48-0.50. I strongly suspect that this early Ford wind tunnel was not as accurate as later ones. For example, the difference between the 1960 Pontiac (0.54) and Olds (0.47) seems way too large, considering how similar they are, right down to the general shape and details of their front ends, never mind the same basic body overall. I simply don’t believe that there was that large of a gap.
The VW’s Cd (accurately being 0.48 in modern wind tunnels) needs to be seen in the context of 1938, when its body was designed. How did it compare to other 1938 cars? Very well. Also, keep in mind that shorter cars inherently are at a disadvantage aerodynamically than longer cars because the airflow tends to stick to the body better on a long one, which explains why very short cars like the SMART have such poor Cd numbers. So comparing the Cd of a short car to a long car is apples to oranges. In any case, the VW’s (actual) Cd of 0.48 was still quite good in the 1960s, some 25-30 years after it was designed without the benefit of a wind tunnel and on a short body.
Here’s the wind tunnel data plot for the Volkswagen.
Here’s the wind tunnel plot for the Oldsmobile. A wind tunnel of that era did not measure Cd per se; it measured drag and lift, and the coefficients had to be calculated from the wind tunnel data. In this case, Heltemes calculated the drag coefficients based on the measured drag at 80 mph and the frontal areas that Ford measured.
Here’s the Pontiac data plot, which is also the one that’s overlaid on the lead image (naturally). Its measured drag was significantly higher than the Oldsmobile at all speeds despite having a slightly smaller frontal area.
Great article!
Aerodynamics (on scale models) were being studied already in the 1930s, I imagine that form was being given priority of function considering the rather poor results of the various cars described
Perhaps the first wind tunnel test of cars was done by K-State in 1927. Their limit was 40 mph because very few cars went beyond 40. They tested a variety of touring cars, roadsters, sedans, coupes and trucks, plus one stripped-down racer without fenders or windshield. The racer had 50 lbs of drag at 40 mph, which is a little better than the results at 40 in your graphs here. Other cars ran from 90 to 160 lbs at 40 mph. Ford Ts were the best of the bunch, and a T roadster with homemade pickup bed was the best of all except the racer. The Franklin, with Renault hood and curved windshield, LOOKED more streamlined but it was among the worst.
The engineers concluded that frontal area was most important, and beyond that the difference was in details that couldn’t be calculated neatly.
Article starts at p 430 of this PDF.
https://books.google.com/books?id=QjlLAAAAMAAJ
I’d like to see the numbers for the Saab 93 and Citroen DS. I’m sure Ford didn’t test them because they were niche cars in the US.
The Cd range typically given for the Saab 93 is 0.30 – 0.32 and for the Citroen DS: 0.34 – 0.36.
That sounds about right. Of course, Detroit wasn’t even trying to streamline their cars.
Karl Ludvigsen wrote in 1970:
Weirdly, John R. Bond’s 1957 paper on the DS doesn’t mention its aerodynamics at all. I’m not sure why.
Considering the most aerodynamic shape is a teardrop, for the most part… when I read “old cars” I was thinking 1930s and 1940s. I wonder how those did in comparison? Many of those had a teardrop looking body, and even the fenders had a teardrop shape. Not only that, the fenders only taking up the space around the wheels, and the main body being narrower, reduced overall frontal area.
I think the Beetle could have done better if it weren’t so short. A longer body does better.
I regret to point out that all of the cars pictured here are 65 years old now, which is “old cars” by any definition I can think of. Believe me, I’m not happy about it either….
On the lighter side, here’s how I’d generalize the aerodynamics of this era of American vehicles.
The rock is less likely to take off into the air — I’m thinking more “Snoopy flying his doghouse after the Red Baron.”
It is interesting that you make such a point about aerodynamic lift. Although I love the GM B bodies introduced in 1977, they really weren’t that comfortable above 65 MPH. After that, the front end lift got progressively worse. I have always believed these cars were designed to cruise at 65 MPH.
“If air pressure over the top of a car is lower than pressure underneath, the car body will start to act like a wing, lifting the car off its wheels!”
Found that out driving an 1984 T-Bird in a strong crosswind. Sideways that aerodynamic body acted like a wing. I had driven lots of boxy vehicles in crosswinds. While the wind may have pushed against them they still felt stable. But in that T-Bird you could feel the body lifting and handling getting unbalanced.
It was also when more aerodynamic cars showed up in stock car racing that cars stared getting airborne going sideways or backwards.
Whenever I read about the the Cd of various cars I realize that what looks aerodynamic to me generally isn’t. It seems to be in the subtle details. The recent article by Roger Carr about the wonderful 69 Alfa Guilia quotes a Cd of 0.34, which is exceptional, but the 4 door sedan looks like a brick. Looks deceive. I had a practical lesson in aerodynamic stability many years ago when I put a 16 foot canoe on top of my 85 Civic Wagon. It made the car very unstable at any speed over 100kph.
Thank you Aaron! This is very interesting to me as I studied aerodynamics with vehicle design. I have therefore spent a lot of time in various windtunnels and more recently with CFD. I worked tuning the Opel Calibra in the University of Stuttgart windtunnel, which held the production car record for a number of years at 0.26cd. At Porsche we had our own tunnel and also used Sauber’s facility in Lucerne.
One thing to note is that windtunnels are variable – one needs to use correction factors when using different tunnels. One also corrects constantly for different barometric conditions and temperatures.
I agree with Paul that the Beetle is usually rated at 0.48 cd. The split screen bus is lower at 0.42 and the Karmann Ghia has an astonishing for 1955 0.37cd, which, along with a smaller frontal area explains why, with the same drivetrain as the Bug the Ghia has an 8-10mph higher top speed.
The biggest surprise for me is the Corvair – it’s combination of low frontal area (almost the same as the bug!) and low cd is really impressive. The Dauphine does well, too.
BTW, belying it’s boxy looks, the Alfa Giulia sedan of the early ’60s had a cd of 0.34, the same as the two decade newer Ford Sierra and lower than the 0.36 cd of that aero paragon, the Citroen DS…
80mph in an Anglia ? I’ve done 65 in one and that was scary enough, although to be fair it was a clapped out old banger by the time I got my hands on it.
The Corvair was probably slipperier than a Falcon because it has no front grille – cf. the Dauphine.
Get a 1930s Tatra in there – and lay down and weep!
I did read once that the Escort actually had a worse front end than the Anglia, but being longer permitted the air flow to smooth out and being lower, actually less frontal area. So it won on the crucial CdA stakes. Some estate cars do the same thing over their sedan counterparts.
The Nash doesn’t surprise me – ze Chermans tested its German cousin, the Borgward Isabella retrospectively and came up with a figure of ~0.40. Pretty averagely good for something 1970s in fact. Borgward’s 2,3 was to have an even more Imperial-alike roofline than it did, but they found the ‘peak’ over the windscreen was costing about 10 km/h so they had to shave it off.
Different wind tunnels give differing coefficients, so one cannot compare apples & oranges, unfortunately. That can lead to confusion.
I’m actually surprised that some of those hideously overstyled 1960s front ends aren’t even worse though, quite frankly.