In a message dated 02/07/2000 7:18:38 AM Pacific Standard Time,
lsr_man@yahoo.com writes:
<<
For all you Ardun and Chevy guys, I've got a
question. Zora Arkus Duntov designed and created
the Ardun hemi conversion for flatheads (a gem I
learned here on the list). It was put into
limited production and proved itself as a
performance getter.
######## Dick & Group,
The Arkus-Duntov Bros. were a small subcontractor for FoMoCo in the late
40's when they realized the dire need for something to mitigate the
overheating problems in Ford trucks (which used the same engines as passenger
cars).
Having had exposure to the Talbot hemi in pre-war Europe, Zora designed
an aluminum hemi head for Ford commercial applications and produced a limited
run of probably a hundred or so. They were advertised to increase the
Flatty's 85-100 horsepower to 170 and could be installed in an afternoon.
The truth was that using stock pistons the c/r ended up at 6:1, the
single 2 bbl. Ford carb located on the stock Ardun log intake manifold was
woefully inadequate, and the valve system left much to be desired. In
addition, the cartridge-fire sparkplug location necessitated over 40 degrees
of ignition advance, overwhelming the capacity of the Ford distributor to
handle starting with limited advance capability.
Soon after the Arduns introduction around 1948-49, Ford replaced the OEM
engine in the F-7 and F-8 trucks with the new for 1949, 337 ci Lincoln
flathead V-8 power plant. This wiped out Zora's dream of the Ardun being a
dealer-installed option. The heads were too big to fit into the engine
compartment of a passenger car, and marginal for a Ford pickup.
At that time, the Bros. Arkus-Duntov sold the whole scheme to either
Stevens (sp?) or the Ardun Power Products Co. who ran the total production to
about 350 pairs and furnished some to whoever was importing the engineless
Allard sports cars to this country from the UK.
When some amateur owner dropped a Kettering Cad OHV V-8 into an Allard,
the Ardun Allard era ended and hot-rodders became the main market for the
conversions.
At this point, Clem TeBow and Don Clark (C&T Automotive) in the LA area
got a set of Arduns and started experimenting on Tony Capanna's Wil-Cap Dyno.
They discovered how to cure the shortcomings of the Ardun, but created a
whole slew of other problems, namely a lower end that would fail regularly
when the horsepower reached 250 on steroids.
By the early 50's the Cad / Olds OHV V-8's were appearing in race cars,
producing more reliable horsepower than the Ardun was capable of. Rumor has
it that when the MoPar engineers were designing the 331 Chrysler Hemi in 1950
they had a 1949 Kettering Cad block and an Ardun head sitting on the design
table. The early MoPar Hemi head is quite similar to the Ardun, and the
intake manifold comes VERY close to fitting the Ardun bolt-pattern. Ask Ardun
Bill Hoddinott who has a 331 MoPar Hilborn bolted to his Ardun in the hiboy
roadster.
By about 1953-54 Zora Arkus-Duntov had gone to work for the performance
wing of GM and was busy changing the Corvette from a 6-cyl. plastic toy to a
ferocious V-8 sport-touring. The SBC was on the drawing board at GM by then,
but Zora helped refine it to what appeared in Chevrolet with the 1955 model
year.
Ironically, Zora helped drive the final nail into the coffin of his
beloved Ardun heads when he refined the SBC into what appeared shortly after
he signed on with GM. Why he didn't push for the SBC to have a hemi
combustion chamber is unknown, but the wedge has survived in American V-8's
when the Hemi combustion chamber dwindled to near extinction (imports
nonwithstanding).
The introduction of stronger crank assemblys for the Flatty has made the
Ardun a much more reliable piece. It is, however, still pretty crude compared
to modern Hemi race engines. The rocker ratio is barely 1.2:1 and the ports
in their stock configuration will only flow about 160 cfm at 25" of water.
Even with the ports moved and modified the intake will only flow about 240
cfm at 25".
COMMERCIAL BREAK*********If any body is still interested in learning
about the history of Ardun, I sell a 70 page paperback booklet that includes
Tom Senter's "Ardun-White-Papers", the original Ardun Power Products
installation instructions and parts lists, the C & T Automotive instructions,
and a reproduced Allard color brochure showing the car with an Ardun
installed. The booklet is $13, post-paid, from me at 25385 Palomares Rd.,
Castro Valley, CA 94552.*************########
Ardun Doug King in Ca.
Then, Chrysler put a very similar layout into production, proving it for
mass production and daily driver use. When Chevy
came out with their V-8, with Duntov being it's
daddy, and the daddy of all that was performance
orineted from Chevy, how come Chevy never put out
a hemi? I mean the true lord and master of hemi
was right there at Chevy. Didn't he ever try to
convince Chev to do a hemi?
= >>
|