Preparing To Take On Speed Records In Two Classes
Back when Henry Ford released the Flathead V8 early in the last century, it was revolutionary in numerous ways. But the power wasn’t exactly revolutionary. The flathead was designed to provide adequate torque while being economical to produce and relatively (at least for the time) durable. Horsepower, unfortunately, was not at the top of the priority list.
In fact, the first examples produced just 65 horsepower, which was 10 horsepower less than the Chevrolet straight-six from the same era. In fact, the most Ford’s version of the flathead was ever able to produce on its own was a measly 110 horsepower.
And that’s the reason why brothers Zora and Yura Arkus-Duntov decided to develop a better-flowing overhead valve setup for the flathead. (If you are wondering, yes, that’s the same Zora Arkus-Duntov of Chevrolet’s Corvette fame.) They formed Ardun – a company named after an amalgamation of their last name – and developed their own overhead valve kit for the flathead. In 1945 they even approached Ford Motor Company, in the hopes of selling the Ardun cylinder head design to the automaker.
But the powers at Ford turned down the offer and rejected the Ardun cylinder, so Zora and Yura decided to produce and sell the engine kits on their own. The big advantage of the Ardun design is the overhead valve arrangement allowed for highly efficient intake and exhaust ports which flowed much more air than the convoluted ports cast into the flathead block. Overhead valves also had the opportunity for greater lift without lowering the compression ratio like it does in a conventional flathead, and finally, the hemispherical combustion chamber makes for a cleaner burn than the OEM chamber.
Doug Kenny’s 1929 Ford Roadster LSR racer. The Ford is slated for two classes: XXF/BFR (Blown Fuel Roadster) and XXF/BFR (Blown Gas Roadster).
Unfortunately, while they did make more power, the Ardun kits did have the same issues that caused the decision makers at Ford to say no thanks. Namely, the bigger cylinder heads added weight, made the engine significantly wider so it would no longer fit in many stock engine compartments, had durability issues (particularly valve seats falling out of the heads after a few heat cycles), and at $500 a set were quite costly for the time period.
Plus, while there were power gains, they weren’t exactly extreme. Depending on tuning, most customers saw a power boost between 25 and 60 percent, with most engines averaging around 160 horsepower.
So the Ardun cylinder head kit never quite caught on like Zora and Yura hoped. Still, they managed to produce somewhere between 200 and 250 pairs of heads and associated parts. And although the Ardun heads never caught on with the mass market, racers almost instantly recognized their potential. It’s their constant improvements that have helped make the overhead valve cylinder heads for the Ford Flathead take on the almost mythical reputation they have today.
These days, those original 200 to 250 pairs of Ardun cylinder heads are as rare as a snowman in Alabama, but thankfully, reproductions are still available. Just be prepared to wring out your wallet. Today, Don Ferguson owns the right to produce Ardun cylinder heads and associated products, and you can purchase a brand-spanking-new pair of heads, shaft-mount rocker arms, valley cover and a few other things for your flathead build. But you’d better be serious, because it’s going to cost you a whopping $16,000 for a set.
Which brings us to the topic of this story. Land Speed racer Doug Kenny purchased a 1929 Ford roadster from another racer that had a supercharged Ardun engine already in it. He and his crew spent weeks tearing the car apart and rebuilding it and even refreshing the engine before taking it back to Bonneville for Speed Weeks back in 2001. But unfortunately, the engine burnt two pistons while on the salt, and Kenny had to come home without setting any records.
For help with the engine rebuild, Kenny turned to father-and-son duo Keith and Jeff Dorton at Automotive Specialists in Concord, NC. After dominating several series in oval track and stock car racing for decades, in the last several years Automotive Specialists has turned their focus to really high-end unique builds, usually either for show cars or for land-speed racing
As we went to press, the Ardun was ready to be fired up. The Roadster hasn’t been to the Bonneville Salt Flats with the new engine yet. These images are from the car’s last outing in 2021.
Because of pandemic-related supply chain issues, it took nearly two years for Kenny’s Ardun to be rebuilt to Automotive Specialists’ standards. Thankfully, we were able to step in just as everything was coming together. Please note that this is not a story about building a flathead with the original Ardun components. In the same vein that racers and innovators built their own highly modified Arduns when Zora and Yura first began selling the heads in the 1940’s, this story is how a smart engine builder is continuing to advance power levels with these iconic heads almost 80 years later.