[aerohead]

Between 1934 and 1937,Chrysler produced the 'Airflow,'which sold as a Chrysler,DeSoto,and Imperial.
The car was designed by Chrysler's chief of research Carl Breer,who's interest in automotive aerodynamics dates to 1927.
Breer hired Dayton engineer Bill Earnshaw who together with Orville Wright developed a small windtunnel to do model tests.
Soon,Chrysler built a larger tunnel in Highland Park,Michigan and Breer became directly involved.
Testing revealed that automobiles had lower drag,went faster,and got better mpg when going backwards.
The 1933 DeSoto sedan which served as the comparative baseline for the Airflow scored Cd 0.683 'forwards',and Cd 0.546 'backwards.'
The 1934 DeSoto Airflow sedan is reported by Chrysler at Cd 0.546.( Cd 0.675 was typical for cars of this period ).
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After the Airflow went on retail sale Breer and his team continued to experiment with aero-modding.By 1934-1/2 Breer had achieved significant results.
In 1939,Chrysler researchers,W.E.Zierer and J.B.Macaulay,Jr.,revealed that they had achieved up to a 50 % drag reduction through aero-mods.
On June 4,1941 James C.Zeder,Chief Engineer for Chrysler,and brother of Fred Zeder,one of the 'Three Musketeers',responsible for the Airflows development,presented a paper on the aero-modding at SAE's semi-annual meeting and in December,after the attack at Pearl Harbor,Hawaii,the work was published as SAE Paper # 410139 "Is It Practical to STREAMLINE for FUEL ECONOMY?"
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The paper gives a breakdown of the methodology used to quantify results.
Chrysler did experience wide discrepancies between windtunnel results and actual on-road performance.Top speed runs were made,throttle-stop runs were duplicated on the dynamometer,and coasdowns were performed when weather allowed.
Original drag data is given in the form of a K-value,borrowed from :
"Engineering Aerodynamics," W.S.Diehl,Ronald Press,1935
"Aviation Handbook," E.P.Warner and S.Paul Johnston,McGraw-Hill Book Co.,Inc.,1935
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The paper lists seven (7) discreet aero-modding permutations within a table,along with the top speed achieved,and mpg,before and after the final mods.
NOTE: On page 3 of the paper,an '8th' condition is cited which is not reflected in the table.This 'condition' reflects a 44-inch ( 1,100 mm ) 'long-tail' 'stinger' configuration which achieved the lowest drag.
If the images presented in the table are close at all to scale,then this condition '8' is not represented and I have included it,merely drawing the longer 'stinger' over the short tail cone depicted.
All the vehicle images to be posted in PART-2 are normalized as to rear axle position to give an easier comparison of mods.
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One of the most important points of the paper is the effect of gear-matching as related to mpg potential from aero-modding.As the sytreamlining reduces the load,the engine moves into a less efficient BSFC.Even though all the Airflows had Borg-Warner overdrives,Breer found himself forced to change the DeSotos ring and pinion from a 3.89:1 to a 2.74:1 ratio to keep the engine loaded.
Hucho,Janssen and Emmelmann warn of the same thing in SAE# 760185 and Gino Sovran in SAE# 830304.
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Here are the data from the table.Al will try to get the images up in PART-2 so you can get a visual on what Breer and his team did.
(1) Standard DeSoto Airflow sedan------------------------------- Cd 0.546
(2) bumper delete, trim stripped,flush windows,rear fender skirts--- Cd 0.500
(3) new front(lights moved behind grille,raked shovelnose,sm. grille- Cd 0.468
(4) tail modded to pseudo-Kamm w/ straight chop,no added length- Cd 0.417
(5) full bellypan and sill fairings/extreme fender radius fillets-------- Cd 0.367
(6) 21-inch ( 525mm ) boat-tail 'stinger'-------------------------- Cd 0.316
(7) false decogramic 5-panel semi-circular windshield--------------- Cd 0.308
(8) 44" ( 1,100 mm ) plan-tapered stinger w/ plex-covered license-- Cd 0.238

NOTE: No mention of mirror delete.No mention of wiper delete.No mention of plex-covered license plate.No mention of headlight relocation.No mention of engine bay air exhauster gravity-damper delete w/ shape and size mods.
These are observed from photos published by Hemmings from Chrysler Historical Photos.
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PERFORMANCE:
Top speed: 84 mph (135 km/h)-------- increases to 99.4 mph ( 160 km/h )
Fuel Economy: 15.1 mpg @ 60 mph ( 96 km/h )----- increases to 22.8 mpg
51 % improvement

11.3 mpg @ 80 mph ( 129 km/h )---- increases to 17.7 mpg
56.6 % improvement
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Zeder mentions,that as of 1941,Chrysler had a Cd 0.238 car of 200-inch ( 5,000 mm ) overall length 'in the works.'
The 1969 Charger Daytona was measured at Cd 0.29
A 1960s Plymouth Barracuda designed for Bonneville has been measured at Cd 0.20.
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The 1934 aero-modded DeSoto,compared to more contemporary vehicles would have the width of a 1957 Mercedes 300 SL
would be 12.7-inches ( 317 mm ) shorter than a Ford F350 XLT Lariat pickup
the height of a 1984 Isuzu Trooper
weight of a 1991 Nissan Pathfinder
and not quite the frontal area of a 1989 Nissan Access minivan.(25.194 square-feet )(2.33 Meters squared ).
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That's about it for the data,we'll see about getting the images up.

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PART-2 ( photos )

I found a copy of '70 YEARS OF CHRYSLER' by George H. Dammann at the used book store.On page 196 was a side view of Breer's aero-modded DeSoto.
He credits John F. Bunnel,Corporate Historian,Chrysler Corp.,and H. Donald Schaerer,Archivist,Chrysler Archives.The photo would be from the Chyrysler Historical Collection.
I've included this image,along with two others,also from Chrysler Historical,which appeared in Hemmings Motor News',Special-Interest AutoS,April/May,1973,No.16,P.19.
These photos are better than the drawings I was working on.
The upper photo depicts the 'short' stinger configuration,the lower-left image depicts the 44-inch 'long' stinger.