The lug nuts for the Hurst wheels used positive tapered seating with a long reach for Hurst's specific design. They were the same size as the OE lug nuts.
"Before making a decision to build the new Hurst wheel," George Hurst said, "we decided to test all the popular makes to determine how good they really were. Test equipment was set up in our laboratory to evaluate the reliability and strength of any wheel."
Hurst utilized the same test equipment and standards as specified by carmakers in Detroit. Hundreds of different aftermarket wheels were tested and not one passed the standards. Two basic tests were used. The first was the Impact Test 2,000-pound, also known as "The Guillotine." In this test, a 2,000-pound metal slab was dropped from a height of either 12 inches or 24 inches onto a wheel mounted on a test stand at a 30-degree angle. According to Hurst, "The damage on a great many wheels showed the inner cores or spiders shattering like glass under the 2,000-pound blow."
Hurst produced a limited run of gold-anodized wheels, which were introduced on the GeeTO Tiger promotional GTO. They're some of the rarest of all Hurst wheels.
The second was the Rotating Fatigue Test. In this test, a wheel was spun at a load of 2,036 lb-ft (which was the Pontiac OE standard for wheel testing) to "exert alternating stresses, or fatigue stress on the wheel." A rod was bolted to the wheel center and an overload of 50 percent was exerted. The wheel was spun to as many revolutions as it could bear before failure. "On the average," Hurst noted, "most wheels tested chalked up revolutions of just over 12,000, less than half the accepted number of revolutions required by the nation's leading independent testing laboratories."
As testing continued, it was obvious to Hurst that an entirely new approach to wheel design and engineering was required. Weight was a major consideration, but Hurst refused to trade strength for lighter mass. George Hurst worked with his engineers to design a wheel that combined both light weight and strength. Hurst turned to Harvey Aluminum, the leading manufacturer of forged aluminum alloy. The use of double-dropped forged aluminum alloy in the aerospace industry had become commonplace, but this was the first time it would be applied to automobile wheels. To ensure a smooth surface for plating, the forgings were coined to provide perfect grain flow in the forging's crystalline structure. The spiders were then coated with HINAC for a clear, preservative finish.
This is the 1965 GeeTO Tiger GTO that was given away by Hurst, Pontiac, and Petersen Publishing Company. The GTO was equipped with gold anodized Hurst wheels, and loaded with a Tri-power and a four-speed that boasted a gold-plated Hurst shifter.
Hurst designed a 14x6-inch rim with a strong cross-section design and a wall thickness wider than any OE wheel used. The rim would then be zinc dichromate plated for both rust prevention and appearance. To attach the forged aluminum spiders to the rim, a load-distributing stabilizer plate was welded to the rim and overlapped the inside spokes of the spider, creating a steel/aluminum "sandwich" to double the wheel strength. Two 5/16-inch high-tensile steel rivets were used per spoke to attach the spider to the rim. A special washer and rubber sealer prevented possible air leaks.
In testing, Hurst's design proved to be twice as strong in fatigue and impact resistance as other custom wheels. It exceeded all OE wheel standard tests and proved to be virtually indestructible in real world applications. After reviewing the wheel's test results, both the NHRA and AHRA approved and sanctioned the wheel for competition.
Hurst chose to introduce the world to his new wheels by bolting them to the Motor Trend Riverside 500 pace car, a 1965 GTO convertible. Dan Gurney won the race and was awarded the pace car by George Hurst.
Hurst engineered the wheels with one of three bolt patterns to fit Ford, GM, and Chrysler products. Plans were announced for 13-inch and 15-inch fitments for a later release, however, those sizes never materialized. Hurst wanted to give his customer the widest range of wheel appearances as possible, so a confusing array of 24 different wheel and beauty ring, and center cap combinations were offered. To that end, the spokes were finished in either a polished highlight in the spoke center, or with a matte finish. All had polished spoke ribs. A primered spider was offered beginning sometime in 1966, which allowed the customer to paint the spokes any color he or she wanted for a totally custom look.
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