THE CAR
Zora Arkus-Duntov was instrumental in the development or promotion of the following breakthroughs that have been incorporated into The Smuggler :
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Vintage ARDUN Engine
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High-lift Camshaft with Solid Lifters
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Forged Pistons
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Vintage Italmeccanica Supercharger
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Fuel Injection with Holley Software
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All-wheel Independent Suspension
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All-wheel Disc Brakes
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Halibrand-style Magnesium-alloy Indy Racing Wheels
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Secret Frame Crossmember Compartment for Gold Smuggling
VINTAGE ARDUN HEMI HEADS
The Zora dream Smuggler is powered by a vintage 1948 - 1950 aluminum ARDUN overhead-valve hemi conversion kit on an original 1953 Ford 24-stud (final version) Flathead V8 block.
Soon after WWII ended, returning servicemen started racing cars at decommissioned air bases, dry lake beds, and salt flats in California and Utah. The engine of choice was often the ubiquitous Ford Flathead, and the racers were always looking for ways to hop-up their cars.
By 1947, Zora Arkus-Duntov was able to begin fulfilling his dream of improving the Ford Flathead and had developed his own conversion kit to give it more horsepower. The ARDUN kit sported heat-treated 355-T6 Alcoa aluminum alloy heads with hemispherical combustion chambers, centrally mounted spark plugs, twin valve springs, high-chromo rocker arms, bronze valve guides, streamlined exhaust ports, and more. (See Appendix A for a full list of ARDUN kit components.) The first series of aluminum heads and valve covers were cast on Long Island, New York (Biblio #11) but production of later heads and valve covers was shifted to England for cost reasons and to get around post-war English restrictions on importing goods into Europe.
Zora's conversion kit was an exotic improvement for the Ford Flathead, propelling those ancient side-valve engines towards a technological par with the best European automotive and aircraft engine designs of the time. (Biblio #12) In February 1947, he released an SAE paper of ARDUN factory dyno tests claiming a horsepower increase from the stock 95 to 175 at 5200 RPM and 225 lb/ft of torque at 2500 RPM for a standard 239 CID Ford block with a compression ratio of 7:1. (Biblio #13) A story in the October 1947 issue of Popular Science also promoted the ARDUN kit for use in trucks. (Biblio #34)
The ARDUN conversion kit's overhead valve design also cured the persistent overheating of the valve-in-block Flathead V8 that was caused by the two ‘Siamesed’ center exhaust ports into a single tube, creating a large heat transfer from the hot gases to the coolant. (Biblio #12)
“The ARDUN engine runs as cool as your mother-in-law’s scowl when she finds you in the local bar and grill on payday.”
--Zora Arkus-Duntov as quoted by Tom Cahill in Mechanix Illustrated, January 1951.
In a 1949 Ford business coupe with the ARDUN head equipment added, Zora claimed a zero-to-60 time averaging 9.8 seconds. In September 1949, Zora raced an Allard J2, the very first ARDUN-equipped racecar, at Watkins Glen, New York (he was in the lead, but didn’t finish due to a locking back wheel). (Biblio #2) In January 1950, the car competed again at Palm Beach Shores. By May 1950, Bob Estes' car with an ARDUN attempted to qualify at Indianapolis, averaging 124 MPH. (Biblio #14)
By April 1950, the ARDUN kit was being advertised in Hot Rod Magazine.(Biblio #37) Through the years, ARDUN-powered cars set records in hundreds of classes. The engine became a legend in its own time. (Biblio #13) The July 1956 cover of Hot Rod Magazine was graced with an ARDUN-powered car. (Biblio #15)
First magazine cover to show an ARDUN:
HOT ROD Magazine, July 1956
According to Tom Senter in the ARDUN White Papers, parts were made for thousands of kits, (Biblio #13) but the final number of heads cast was only 200 – 250. (Biblio #13,15) Serial number stampings were not sequential, and some numbers are much higher than the actual number of heads cast. (Biblio #11)
In the 1950’s there were a number of ARDUN failures (and likely also Italmeccanica Supercharger failures) due to inadvertent over-revving of engines. Tachometers were still not in widespread use at the time, so Duntov solved the problem by installing low-tension valve springs which induced float at 4500 RPMs. Thus was born the first mechanical rev limiter. (Biblio #19)
German engineer Otto Schulze had registered a patent for a mechanical tachometer way back in October 1902. Sun Electric Corporation in Chicago, IL was formed in 1931 and made an electronic tachometer. (Biblio #16) But they didn't become popular until the early 1950's. As shown in the 1952 issue of Hot Rod Magazine, the 1952 version of the So-Cal Speed Shop Lakestar belly tank streamliner was an early adopter with a Sun tachometer centered in its gauge cluster. (Biblio #17,36)
Zora would be delighted The Smuggler is equipped with a modern electronic tachometer.
History of The Smuggler’s Vintage ARDUN Heads
The Smuggler’s ARDUN engine was purchased in 2018 as a complete engine from Art Redford in Gig Harbor, WA. He had obtained it in 2002 from the estate of Pat Hart, a vintage automobile enthusiast and racer in Redmond, WA by trading his 1947 Knucklehead Harley motorcycle for it.
Pat Hart’s sons recall that the ARDUN had likely been acquired from Dean Moon of Moon Speed Equipment in Norwalk, CA. Dean Moon and Pat Hart were friends and worked together between 1976 – 1983 on Hart's 1948 MG-TC that had the smaller version ARDUN 60. They also worked on several other car projects along with other hot rodder legends Doane Spencer (’32 Roadster), Alex Xydias (So-Cal Speed Shop), Fred Larsen (Moon Speed Equipment, Larsen & Cummins Streamliner), and Dick Kraft (The Bug).
The Smuggler sports vintage Second-Series 1948 – 1950 aluminum ARDUN hemi heads with center exit water outlets. A plug is present in the front of each head at the site where the water outlets were originally placed for the first series of heads cast on Long Island. (Biblio #12) The Smuggler's vintage valve covers are the second of three types, but the plugged front water outlets suggest they may have been an early casting. (Biblio #11) The original NEW YORK lettering on second-series valve covers was milled off and a brass plaque added that read either "Allard" or "Made in England.” (Biblio #12)
The Smuggler's heads showing serial numbers 481 and 529
Plug on front of The Smuggler's head that corresponds to site of water outlets if First-Series heads.
There is the stamped code DTD424 on the heads that indicates the Aluminum-Silicon-Copper alloy material specification originally issued by the British Air Ministry Directorate of Technical Development (DTD) in January 1940 (and used in the Spitfire and Jaguar XK series engines).
There is also the stamped code (TZ 63CLS) on the lateral surface of The Smuggler's heads. Noted Hot Rodder, Ron SanGiovanni (aka Ronnie Roadster), feels this may be someone along the way just personalizing their heads. (Biblio #11)
The Smuggler’s heads showing stampings DTD424 and TZ63CLS
The Smuggler’s ARDUN was rebuilt by Ryan Falconer Racing Engines in Chino Valley, Arizona. Falconer replaced the crankshaft with a SCAT crankshaft to get rid of oiling issues associated with the original babbitt bearing design. The pistons were replaced with Ross forged pistons with Total Seal rings.
The Smuggler’s ARDUN has a Bore of 3.375” and a Stroke of 4.230” (302 CID) with a compression ratio of 8:7.0. Brake horsepower (with Italmeccanica Supercharger installed) was measured by dyno at 296 at 5000 RPM with torque at 358 lb/ft at 3500 RPM. (Biblio #18)
High-lift Camshaft
with Solid Lifters
One theory of the derivation of the term, “Hot Rod,” is that it refers to replacing the engine’s camshaft or “rod” with a higher performance “hot” version. Then it isn’t just an old jalopy, it is a bonified Hot Rod!
Zora was interested in camshaft design, but did not offer one with his ARDUN conversion kits. It is likely he did place a hotter cam in his 1949 Allard J2 that raced at Watkins Glen because it sported three Stromberg carburetors. (Biblio #11)
Later at GM, Zora developed his camshaft design into what became known as the Duntov 30-30 high-lift camshaft that bumped horsepower (part no 3736097, $27.95 at the parts counter) (Biblio #13). He used this camshaft while setting the flying mile record at Daytona by blasting past 150 mph in a V8-powered ’56 Corvette. (Biblio #7)
As Arkus-Duntov would have wanted for his dream gold smuggler in 1937, The Smuggler sports a hotter camshaft with the solid lifters he advocated.
Forged pistons
Zora Arkus-Duntov was responsible for using the first forged pistons in a production American automobile engine. (Biblio #19) Forged pistons employ a single lump of billet alloy which is stamped by the use of a die. The process of forging compresses the molecules inside the alloy, resulting in a denser surface area compared to a cast piston. Forged pistons can withstand a higher compression ratio, enabling the engine to rev higher and produce more power.
When Chevrolet general manager Ed Cole wanted the 348 cubic inch Chevrolet engine made more competitive on the super speedways, it was Arkus-Duntov who developed the high-performance parts, including the first forged pistons that put a Chevrolet in the Daytona 500 winner’s circle in 1960. (Biblio #19)
Zora would appreciate The Smuggler’s forged Ross 2618T-61 aluminum-alloy pistons.
Vintage Italmeccanica Supercharger
During his final year of training at the Technical University of Berlin in Charlottenburg, Zora published (under the name Zora Arkus) a lengthy article about the dynamics of the supercharged engine in the 27 May 1934 issue of Motor und Sport, (Biblio #20) Germany’s most prestigious automotive publication. (Biblio #2) So, at age 24, Zora was a published expert in supercharging (even before he became a gold smuggler).
Superchargers improve an engine’s breathing and performance by forcing air into the cylinders, as opposed to allowing the air/fuel mixture to be drawn in by the vacuum created by the moving piston on its intake stroke. Forcing in the air and fuel creates a denser mixture for compression and then combustion. (Biblio #21) A Roots type blower (named after the brothers Francis and Philander Roots who created and patented the device in 1850 to help melt iron in their Oxford, Ohio manufacturing mill) (Biblio #22) uses rotating interlocking lobes rather than a fan to move the air. It is known as a positive-displacement blower. This method has the advantage of producing increased power across the entire RPM range.
From the early teens up to WWII, European Grand Prix racing cars typically had Roots-type superchargers. Hot rodder Barney Navarro is usually credited with the first US racing use of a supercharger (from of a WWII landing craft) in 1948.
The Italmeccanica Co. of Torino, Italy filed for a Swiss patent on March 24, 1947 and started making the supercharging kit that was to become all the rage in America starting in the 1950’s. (Biblio #21,23,36) The “easy to install” beautifully crafted $467.50 kits for Flatheads were first advertised in the April 1950 issue of MOTOR TREND Magazine. (Biblio #24) They claimed to pump 7-9 PSI and increase horsepower by 62%. (Biblio #25,26) In 1952, the company got into serious financial trouble, reorganized, and renamed their company and product S.Co.T. (which was assembled in New Jersey). Hot rodder and Italmeccanica rebuilder, Ron SanGiovanni (aka Ronnie Roadster), estimates Italmeccanica made around 2000 blowers in nine different styles. (Biblio #11)
We suspect Zora would approve of The Smuggler’s original Roots-type Italmeccanica Supercharger (Serial No. F/397) built in Torino, Italy between 1949 -1951.
1950 ad in Motorsport Magazine (Biblio #27)
History of The Smuggler's Italmeccanica Supercharger
The Smuggler’s Italmeccanica Supercharger (Serial No. F/397) was purchased in 2018 from Joe Abbin of Roadrunner Engineering in Albuquerque, NM. Joe is a Flathead Ford enthusiast and has written numerous publications, including, Blown Flathead and Flathead Ford V-8 Performance Handbook. In addition to engine design analysis and testing, his company sells supercharger kits. Joe had the Italmeccanica rebuilt/improved by Ron SanGiovanni (aka Ronnie Roadster) in 2005 and used it on the display engine in his shop. He says he never got around to mounting it on his ’40 Ford coupe. (Biblio #10)
Blown Flathead by Joe Abbin, previous owner of The Smuggler's Italmeccanica Supercharger
Joe Abbin acquired the Italmeccanica supercharger from Walt Ingalls in Everett, WA in August 2005 (trading it for one his company’s blower kits).
The Smuggler’s Italmeccanica Vintage Supercharger
Fuel Injection with Holley Software
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The Smuggler's AutotrendEFI with Holley Software
Zora Arkus-Duntov created the first successful fuel injection system offered for production American cars. (Biblio #7) Having spent his formative years racing in Europe and the USA, Zora knew that hard cornering tended to starve carbureted engines due to fuel sloshing back and forth, so early fuel injection was developed by Mercedes and others in Europe.
When GM management decided that fuel injection had to be introduced in 1957, it was the efforts of Zora Arkus-Duntov and his staff that got the 2-year project completed on time (despite a major setback in April 1956 when Arkus-Duntov broke his back in an accident at the GM Proving Grounds in Arizona). (Biblio #7,19)
GM’s fuel injection program was started with the goal to reduce unburned hydrocarbons and improve fuel efficiency. Zora was initially disappointed when early tests of his prototype did not show any difference in power output compared to carbureted engines. However, he was surprised to find that fuel-injected cars could accelerate 9% faster than carbureted cars: “The spectacular increase in vehicle performance with otherwise identical dynamometer power can be attributed to the ability of fuel injection to maintain the best power mixture throughout the transition.” (Biblio #7) An added benefit of fuel injection was the ability to run camshafts with less vacuum at idle, higher lift, and more duration for more top-end power. Zora’s efforts resulted in the 1957 “Fuelie” 283, the first domestic production engine to achieve one horsepower per cubic inch. (Biblio #28)
After mandatory GM retirement at age 65 in 1975, Zora began consulting for Holley Replacement Parts Division. He developed the Pro-Dominator 2X4-barrel race manifold and the Z-series intake manifold. (Biblio #19,32)
Our Zora dream Smuggler’s engine is fed by an AutotrendEFI electronic fuel injection system that looks like dual period Stromberg 97 carburetors (standard equipment on Flathead V8s from 1936-38 and named after the 0.97-inch bore diameter). Zora would likely be proud that The Smuggler's AutotrendEFI uses Holley software designed by the firm where he consulted after retiring from GM.
All-wheel Disc Brakes
The Smuggler's front and rear disc brakes with Kinmont covers
Arkus-Duntov long considered drum brakes to be a limiting factor in achieving automotive high-performance. His team at GM developed the first 4-wheel disc brake system in a domestic production car. (Biblio #2) In 1965, he had convinced GM management to incorporate 4-wheel discs into the C2 Vette.
Naturally, Zora would want his dream Smuggler to utilize 4-wheel disc brakes. He would likely be happy with our choice, first patented by Joseph M. Milan back in 1936 (based on mobile World War I German heavy artillery brakes) and used for the first time in an Indy 500 race in 1941. After WWII, racing enthusiasts Bill and Ralph Kinmont, improved on Milan’s concept and started selling their distinctive Kinmont Disc Brake, which quickly caught on with racers and hot rodders.
The Smuggler uses 4-wheel disc brakes and period-appearing Kinmont Safety Stop brake covers.
All-wheel independent suspension
Zora Arkus-Duntov was involved in developing all-wheel independent suspension as far back as the late 1940’s by working with his friend, Sydney Allard, to help develop the British company’s 1949 J2 Prototype. The car had an independent front suspension (IFS) created by cutting a stock Ford I-beam front axle in half and pinning it.
Allard and Arkus-Duntov also converted a Ford rear end to an early form of semi-independent rear suspension called the De Dion Tube for the car. (Biblio #29) The Allard J2 Prototype was shipped to New York for the first ever installation of ARDUN heads and valve covers in a racecar. (Biblio #11) Zora raced the car at Watkins Glen on September 17, 1949.
By 1955, Arkus-Duntov was making significant chassis changes at GM: “The main objects of suspension changes were to increase high-speed stability, consistency in response to the steering wheel over a wide range of lateral accelerations and speeds, and improvement of power transmission on turns.”(Biblio #7)
Zora was also responsible for the 1963 C2 Corvette's independent rear suspension design. He was able to achieve the design and incorporation of both independent front and rear suspension into the very first year of the C2. It was so well designed that it persisted relatively unchanged through 1982, the last year of the C3. (Biblio #2)
Similar to the IFS Zora built for his 1949 Allard J2 , The Smuggler utilizes the EvoAxle, an independent front suspension that was developed by Nate’s Hot Rod Garage to look like a stock Ford solid I-beam front axle.
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The Smuggler's EvoAxle Independent Front Suspension
Our Zora dream Smuggler also utilizes a custom independent rear suspension (IRS) developed by Nate's Hot Rod Garage and Mike Martinez at Diamondback Machining to look as period as possible. Several Corvette parts were utilized in the IRS as a tribute to Zora Arkus-Duntov. It is coupled to a Winters quick-change rear end.
The Smuggler's EvoAxle One-off independent rear suspension coupled to a Winters Quick-Change rear end
The Smuggler’s front suspension also uses period-appearing lever-arm Houdaille dampers from Apple Hydraulics. Nate's Hot Rod Garage designed the custom damper arms.
Frenchman Maurice Houdaille was awarded patents for rotary-vane and lever-arm hydraulic dampers in 1906, ‘07, ‘08, and ‘09. Hydraulic dampers had an advantage over friction devices because they resisted sudden movement but allowed slow movement. They also dampened movement in both directions (“double acting”). Houdaille lever-arm dampers were standard equipment on Fords between 1928 – 1948 (Biblio #30), including The Smuggler before its transformation.
The Smuggler's Custom Front Houdaille Lever-Arm Dampers
Halibrand-style Magnesium-alloy Indy Racing Wheels
Ted Halibrand was an aviation engineer during WWII who put his knowledge to use as a Midget racer after the war. He knew that magnesium, alloyed with aluminum and zinc, created brutally strong yet surprisingly light parts. He cast his first set of light-weight magnesium-alloy wheels in 1946 and formed Halibrand Engineering in Culver City, CA a year later.
The first cars to exceed 140, 150, 160, and 170 mph qualifying laps at Indy 500 all wore Halibrand wheels. Starting in 1951, every Indy winner for the next 16 years ran Halibrand “Mag” wheels. SEMA inducted Halibrand into its Hall of Fame in 1983. (Biblio #31) He died in 1991.
After going through a series of owners, the Halibrand name was acquired by Holley in 2021, the company Arkus-Duntov consulted for after retiring from GM. Zora Arkus-Duntov, through his racing experience, was familiar with magnesium-alloy wheels and advocated them for GM. He even used them on his CERV-1 engineering vehicle. (Biblio #2)
Arkus-Duntov in an official GM portrait with the CERV-1
The Smuggler utilizes true magnesium-alloy (“Mag”) Halibrand-style Indy racing wheels (Front 16 x 5, Rear 18 x 7). Real Rodders Wheels in Ventura, CA let us have one of only 20 magnesium Indy II sets they produced in the Halibrand style.
The Smuggler's Front and Rear Halibrand-style Mag Wheels
Secret Frame Crossmember Compartment Near the Rear Axle for Gold Smuggling
Of course, The Smuggler also has a covered secret gold-smuggling compartment in a crossmember near the rear axle as a tribute to Zora Arkus-Duntov.
The Smuggler’s Secret Gold Compartment
Other Smuggler Build Features
Car History:
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Started as an original complete and running 1929 Model A Ford Coupe
Inspiration:
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Zora Arkus-Duntov: gold smuggler and iconic automotive engineer
Engine:
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Vintage 1948 - 1950 ARDUN heads and rocker covers on 1953 24-stud Ford Flathead block:
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Rebuilt by Ryan Falconer Racing Engines
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High-lift camshaft with solid lifters
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Forged pistons
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Previously owned by Dean Moon
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Vintage 1948 - 1950 Italmeccanica Supercharger:
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Rebuilt by Ron SanGiovanni (Ronnie Roadster)
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Smoothed block surface
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Finned high-capacity oil pan (Ferguson)
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Fuel injection with period-appearing Stromberg carburetors (AutotrendEFI)
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Custom fuel lines
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Custom upholstered “luggage” fuel tank
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Magneto-appearing distributor (AutotrendEFI)
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Custom electric line covers and clamps
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Powermaster PowerGEN alternator
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Custom alternator mount (Diamondback Machining)
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Custom pulley set up with smaller water pump pulleys
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1932 Ford radiator shortened 2” (Walker)
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Custom radiator tubes (Ryan Linder):
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Hidden water temp sensors (Ryan Dotzler)
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One-off custom exhaust (Ryan Linder):
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Exits through frame with custom lip
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Transmission:
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1969 Ford C-4 automatic
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Smoothed surface
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Custom bell housing adaptor (Ford-O-Matic)
Chassis/Suspension:
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Pinched and boxed 1932 Ford rails
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Custom splitter bar (Diamondback Machining)
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Custom center cross member
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Custom motor mounts
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Split Wishbones and Ladder Bars (Johnson’s Hot Rod Shop)
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All-wheel independent suspension:
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Custom IFS (EVO-AXLE, NHRG)
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One-off IRS (EVO-AXLE, NHRG, Diamondback Machining)
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Front Houdaille lever-arm dampers (Apple Hydraulics):
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Custom embedded frame mount
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Custom lever arms (Leading Edge Machine & Design)
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Rear coil-over shocks (Ride-Tech)
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All-wheel disc brakes (Wilwood):
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Front Kinmont-style brake covers (Johnson’s Hot Rod Shop)
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Custom rear Kinmont-style brake covers (Diamondback Machining)
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Wilwood master cylinders under dash
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Quick-change rear differential (Winters)
Cowl Steering:
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Custom Pittman and Steering Arms (Leading Edge Machine & Design)
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Electra-Steer electric power steering (UniSteer)
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Custom steering wheel (original style) and steering column drop (Diamondback Machining)
Wheels / Tires:
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Halibrand-style Indy magnesium wheels
(F 16 X 5, R 18 X 7) -
Coker Excelsior Stahl Sport shaved tires
(F 500R16, R 700R18)
Electrical:
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Dual 6-volt Optima Redtop batteries
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American Autowire wiring harness
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Self-cancelling turn signals
Body:
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Top chopped 4” (back window chopped 3”)
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Rumble seat added, with custom drip trays
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Front visor raised ½” and welded to body
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Steel roof insert under period cloth look
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Drip rail shaved but functional
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Customized 1932 grill shell (dropped 2”)
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Custom Pines Winterfront Grille vanes (Alumicraft)
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Frenched custom grill emblem
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Custom fan shroud (Diamondback Machining)
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Vintage 1932 Guide Headlights with original turn signal lenses
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Custom firewall
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Custom door beltline
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1936 Ford exterior door handles
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LimeWorks rumble seat handle
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Power windows (Nu-Relics)
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Custom license plate surround w LED lights (Diamondback Machining)
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Custom 1948 Ford tail lights with custom lenses and LED back up lights (Diamondback Machining)
Paint:
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Custom color paint mix with pearl
(PPG Envirobase)-
Color: Roselle Red (named after Beth’s home town)
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Painted by Nates Hot Rod Garage
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Interior:
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Custom distressed two tone leather (Armando’s Custom Upholstery)
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Customized original 1938 Ford dashboard
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1936-style crank-out windshield
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Custom dash knobs, interior window cranks, 1932-appearing interior door pulls, and shifter boot surround (Leading Edge Machine & Design)
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One-off dashboard gauges and tachometer with boost gauge (Classic Instruments)
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Custom shift knob with 1929 French coin (Rich Tanquary)
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Custom Sapele headliner inlays
Other:
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Hidden compartment in frame crossmember near rear axle for smuggling gold
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Nickel Plating by Jon Wright’s Custom Chrome Plating
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“Rule of 3” used throughout the build, including:
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Pines Winterfront Grill vanes
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Firewall
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Inner rear fenders
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Splitter bar
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Trailing arm mount
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Rear differential mount
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Steering wheel rim
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Dash knobs
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Seat and door panel pleats
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Appendix A: ARDUN Conversion Kit Contents
Hot Rod Magazine, July 1956 (Biblio #15)
Pair of heat-treated cast aluminum alloy heads with hemispherical combustion chambers, a centrally located spark plug, radially inclined overhead valves, and aluminum-bronze replaceable valve guides and valve seats.
1.875-inch diameter intake valves
1.5-inch diameter exhaust valves
Dual valve springs
Adjustable chrome vanadium steel rocker arms
Forged steel pushrods
Special lifters (solid)
Cast aluminum intake manifold
Cast iron exhaust manifolds (the article mistakenly says aluminum)
Aluminum rocker arm covers
An aluminum plate to fit over the Ford valve chambers
Plates to cover the Ford exhaust valve ports
8 machined brass rods to use as spark plug extenders. (Biblio #11)