<VV> History: Duntov and LM rear suspension
James P. Rice
ricebugg at comcast.net
Thu Mar 3 15:22:19 EST 2016
All: Just a FYI and clarification of some Corvair history.
It has been said: "When an article appeared in an enthusiast magazine early
in the 1960 model year reporting on a race of compact cars where a Corvair
rolled over, Duntov took it upon himself to develop suspension upgrades for
The race in question was in a 6 hour at Castle Rock in the fall of 1959,
exact date unknown right now. I have the article from the R&T March 1960
issue. The flip over was due to the left rear failing mid-corner and
digging into the track surface. Off hand, I do not know how many tires
faired and/or how many of the three Corvairs flipped. I seem to remember it
was just one car, and then the team changed both rear tires on each gas
stop. I do know the tire issue was limited to one brand of tires. They
were newly designed and constructed street tires specifically for the
Corvair. That Duntov "fixed" the situation with serious camber and spring
changes and better tires for the following Sebring and Daytona events is
well documented. See the attachment in my last posting. After these 3
early races, sedan road racing mostly evaporated from this country until the
It's also been said: "It was also Duntov who took the principles behind his
IRS for Corvette to develop the rear suspension that debuted on the '65
Corvair." This subject has come up before. The IRS rear suspension on the
LM Corvair, or the principles behind it, did not originate with Dontuv's IRS
on the '63 Vette.
This IRS configuration was introduced by Eric Broadly on his front engine
Lola Mk 1 small bore (1100cc) sports-racing car early in the 1958 racing
season in England. He then used it on the front engine Lola Mk2 Formula Jr
in 1960 and the rear engine Mk3 F-Jr in 1961. Colin Chapman copied the
design in 1960 for his rear-engine Lotus 18 formula car and Lotus 19
sports-racer. It may be the only thing Colin Chapman ever copied. Jaguar
copied the configuration in 1959 on the prototype E-type Jaguar, the E1A.
It was followed by the E2A, which was raced by American Briggs Cunningham's
team at LeMans and elsewhere in 1960. The configuration was then used for
the production E-type, introduced in 1961.
Duntov used the configuration on his CERV 1 open wheel car, which debuted in
late 1960. Chevrolet R&D participated in the CERV 1 creation. The IRS
configuration was used on the 1963 Corvette, introduced in the fall of 1962.
We do not know if Duntov had any direct involvement in the 1965 Corvair's
IRS. Chevrolet Production Engineering certainly had the talent, and
undoubtedly access to the prints, for the IRS configuration. I have no idea
if any of the Corvette and Corvair IRS parts are interchangeable. But I
Thus, the LM Corvair's IRS configuration originated in England via Eric
Broadly's 1958 Lola Mk 1, not with Duntov or his principles. So far as I
know, only Jaguar and Chevrolet used the configuration in production cars.
IIRC, the Corvette use it until the C4 entered production sometime in the
early 1990's.(?) Jaguar also used it on all their production cars for a
really long time, maybe until the XK-8 came on the scene in about 1996. I
lost interest in Jaguar production cars after the E-type went out of
production. But their Group C and IMSA GTP cars were really good racecars.
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