As a engineering student at the Chrysler Institute 1958-61, I was permitted to study reports in old files (while on a three-month student assignment to an Engineering Improvements Committee). In an experiment from about 1934, a slightly modified Airflow Crown Imperial sedan was equipped with the huge nine-main-bearing inline eight and high compression (about 6:1) Red Head, with 380 cubic inches of displacement. It had overdrive and slight modifications of the body to reduce air drag (smoothed out the headlamp eyebrows, etc.). This was clocked at well above 114 mph! It now sounds rather improbable, but I remember reading this report with absolute clarity after almost a half century.
Even Virgil Exner understood aerodynamic principles, though production cars did not show many of the existing knowledge. Still, some used the information that was out there. Thomas Osiecki noted that Bob Osiecki's Chrysler-powered “Mad Dog IV” set a world speed record of 181.561 MPH at Daytona International Speedway in 1961, largely through aerodynamic improvements.
Russ Shreve wrote:
In 1964, I was involved in the design of a very advanced race car concept for JC Penney, which wanted to get into International Sports Car racing. One of the key features of their car would be better aerodynamics.
In early 1965, I rented the University of Michigan wind tunnel for extensive tests. I hired University of Michigan-associated aerodynamicist Jim Amick to manage the tests and compile data into a report. Ron Martin built the wind tunnel models, and worked with Amick between runs making changes.
Amick's final report had a unique solution...The Wing.
Penney did not continue their interest in a race car, and following a breakup with my partner, he took a copy of Amick's Wind Tunnel Report to Texas car builder and driver Jim Hall, in exchange for a job.
In 1972 Larry Shinoda stopped by my house; he was directly involved in the GM association with Jim Hall, and I showed Larry the original Amick report. Larry confirmed my partner had given the wind tunnel report to Hall, and that Hall was skeptical. Per Larry, he himself had been thinking of similar ideas, and when he read Amick's report realized they had been proven in a wind tunnel. It was Shinoda that convinced Hall it was worth a try.
There is little doubt Hall and Chaparral took race car aerodynamics well beyond Amick. However, I think it is time the world recognized the idea did not originate with Hall. The credit should go to Jim Amick.
Even before the Daytona, the Charger had been tuned for aerodynamics with the special Charger 500 model. As Burton Bouwkamp wrote,
The Ford Talladega showed up at the Atlanta race in the Spring of 1969. It was built specifically for NASCAR racing and motivated us (Chrysler) to design and build the “winged warriors” (Charger Daytona and Plymouth Superbird) for NASCAR racing.
Bob Rodger, our Racing Director (who worked for me at that time) came back from the Atlanta race and said, “NASCAR has gone ‘funny car’ racing.” He said that we should design and build the ultimate race car and forget how practical it was or how it looked because we only had to build 500 of them to be approved by NASCAR as “stock.” I got Corporate approval to do that and we developed and built 500 Charger Daytonas in 1969. Creative Industries built the cars for us.
Burton continued, in his history of the Dodge Charger:
During the 1969 model, we added two aerodynamic models to reduce aerodynamic drag and improve the performance of the Charger on the longer NASCAR race tracks. At the beginning of the year we added the Charger 500 model. We changed the tunnel roof backlite to a flush fast roof line and we pulled the grille forward so that it was not recessed. Actually, this input came from our race teams. ... From February 1 until September 14, Dodge won 15 races against Ford's 22 wins. Not a winner but we were at the ballgame. With the debut of the second aerodynamic model in September 1969 - the Charger Daytona - at Talladega, Alabama, it was a new ballgame. From September 14th through the next year we won 45 out of and the next 59 races.
[Burton later wrote:] In 1970, we built 1500 Plymouth Superbirds because NASCAR had upped the requirement and Plymouth dealers wanted a competitive race car (for Richard Petty). I think Mercury built a “Cyclone” aerodynamic model for NASCAR but I don't remember whether that was 1969 or 1970.
With these models Chrysler dominated NASCAR racing for the next 18 months. We won 75% of races overall - and all of the long track races. In 1971 NASCAR changed the rules and limited the Talladega/Cyclone and our “winged warriors” to a 300 cubic in engine. We parked them because even with the aerodynamic shape we couldn't compete against cars with 426 cubic inch engines. So we went back to regular production “stock” bodies and 426 cubic inches for NASCAR racing.
Not
all testing took place in wind tunnels. Greg Kwiatkowski wrote, “My
car, DC-93, (also known as #88 later in life), was used at the
Huntsville Airport for coast down studies on the new ‘wing.’ They’d run
one way, turn around and run back, averaging the numbers out to get rid
of any spurious input [e.g. wind.]” In essence, if you take it up to
speed, then put it in neutral, and measure the time it takes to slow
down — or the speed after a certain distance — you can get a rough
measure of drag under real life conditions, including the road going by
underneath. Mr. Kwiatkowski added, “The front of the #88 cone/lower valance is sealed all the way back to the engine cross member; what I have seen of the #43, #71, #7 and ‘show car’ #6, that is not always the case. Larry Rathgeb told me that was very important to the aero of the wing car design for the race track. Engineering told the teams the chassis setup, gearing, and other ‘tricks,’ but you can’t make them all implement the suggestions. ...
“The ‘69 race Daytona package got the front lift of a standard Charger to zero, from 1,200 pounds at race speeds. A bigger front spoiler, further forward, would make some downforce – relative to a no lift condition. The rear wing would be used for down force and to balance the car, aero wise. To get the same effect with a rear spoiler would cause a lot of drag! The spoiler would have had to be well beyond the NASCAR limitations of 3 inches. Overall, the car would have lost top velocity in the straights. So, it would have entered the corner at a slower speed. A lose-lose situation. This is why the still-born King Cobra could not be driven fast. It was loose in the corners with the maximum allowed spoiler of that time period. Now, that car had front downforce and rear lift!”
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