September 30, 2022

The early days of NASCAR involved a very thin rulebook that gave engineers and crew chiefs plenty of leeway to misbehave. The most notorious of these was Henry “Smokey” Yunick, who has been credited with most of the thickening of this rulebook since then. He was a stock car racing team leader, builder, driver, engine builder and car designer, but above all an engineering genius. He shook up stock car racing in the 1960s with his bold—often obviously off-the-beaten-track—interpretations of the rules and regulations governing car configuration.

Cheating is ubiquitous in motorsport; I’ve included the quotes only because it’s not a reference to blatant disregard of the rules. Rather, it is a reference to clever readings by rulebook engineers. The saying “If you don’t cheat, you don’t try”, is often thrown around in sporting circles and is still applicable in motorsport. However, Smokey Yunick didn’t make a name for himself by cheating and blindly hoping no one would notice. He took the regulations very literally; anything they didn’t explicitly forbid was off the table. Additionally, he had no formal training in race car design. Call her fiddle hacks if you will, cheats if you prefer, but here are some of her best.

    Smart fuel line

    RacingOneGetty Images

    NASCAR officials once removed the fuel tank from Smokey Yunick’s race car after suspecting it was getting suspiciously good fuel mileage. To their surprise, the fuel tank itself was compliant with regulations but was vented via an 11-foot-long fuel line with an inside diameter of 2 inches. This meant that Yunick could store an additional 5 gallons – yes, gallons – of gas in the fuel line alone.

    Many NASCAR historians say Smokey returned to his nearby Daytona Beach store after the tank, still removed from the car, passed a basic visual inspection. Other stories only mention him returning to his stand. But, given his antics, we wouldn’t be surprised if either of the big stories were true.

    Dribbling fuel tank

    1940s Male Hand Pumping

    H. Armstrong Roberts/ClassicStockGetty Images

    Smokey wasn’t scared off after NASCAR discovered his anaconda fuel line. If you could pass the technical inspection without the authorities noticing that things were going wrong, you were practically golden. So he installed a larger reservoir and stuffed a basketball into it, which made up for the difference in volume. Before the race, he popped the basketball and filled the tank with even more fuel. More fuel means more mileage and less time spent refueling in the pits.

    Freeze-cold gas

    smokey yunick and jim rathmann

    RacingOneGetty Images

    Your parents were right when they told you to fill up in the morning when it’s cold. Fuel contracts at lower temperatures, which means you get more for your dollar. That’s why Yunick cooled the fuel – so much so that it almost froze – before refueling his race cars so he could put more in the tanks and those cars could travel farther than competition. As the cars clocked up laps, the fuel warmed up and expanded, meaning drivers could squeeze more mileage out of a regulation-size tank. However, NASCAR took off, eventually enforcing a minimum temperature for racing fuel.

    Exhaust Manifold Porting

    yunick smoky

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    NASCAR regulations of the 1970s prohibited engine builders from drilling out exhaust manifolds to enlarge the passages. So instead of using a drill, Yunick ran an abrasive compound through the manifold to widen the ports and passages. There was nothing in the rulebook that said you could do it, but also nothing that said you couldn’t..

    Headers are actually a big deal when it comes to creating great power; they capture the exhaust gases from each cylinder and condense the passages in one or two pipes. Their job is to facilitate the expulsion of exhaust gases out of the cylinder itself. The easier you can squeeze air out of the cylinder head, the faster you can reintroduce air. More air inside the cylinder head means you can add more fuel and spark, so more power.

    Chevrolet Chevelle Magnum Opus

    mario andretti yunick chevelle daytona 1966

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    Heading into the 1967 NASCAR season, Yunick had worked hard over the winter months to build one of the most technologically advanced production cars the sport had ever seen – many historians allude to the fact that his Chevy Chevelle was 7:8 scale. However, rather than simply installing a smaller body on the same chassis, Yunick sculpted the exterior of the existing car to cut through the air more effectively.

    NASCAR is short for National Association of Stock Car Auto Racing, which means every car started out as “stock,” or how you and I could buy it from the dealership. The cars you saw in Yunick’s time were actually modified streetcars. This turned out to be a big advantage for involving grassroots competitors in races.

    dick hutcherson and smokey yunick

    RacingOneGetty Images

    But for Yunick — and just about every other NASCAR crew chief — playing by the rules meant leaving speed on the table. There’s a lot that isn’t known about his 1967 Chevelle race car, but many say there’s no original panel that hasn’t been altered. While it might look relatively normal from the outside, it couldn’t have been more different.

    Starting with the front fascia, the bumper has been fitted tightly to the front fenders and bonnet to optimize aerodynamics – all door handles have also been filled in and leveled out to improve aerodynamics. Yunick completely redesigned the rear suspension with the shock and spring mounted vertically and (essentially) behind the rear axle. Compared to the conventional truck arm setup the car would have had, this setup made it much easier to handle thanks to the longer spring base (or the distance between the springs on the left and right sides of the axle ). Finally, one of the most dramatic changes was that Yunick actually moved the driver’s position to the left side of the car to improve cornering on ovals.

    Life after motorsport

    Smokey had a knack for giving NASCAR officials a headache. However, his exploits were not limited to the racetrack alone. Far from there. In 1955, he played a key role in the development of Chevrolet’s small-block V8 engine – the basic design principles are still used in racing today.

    Farther outside the racing circle was the hot steam engine, which almost revolutionized internal combustion as we know it. Yunick basically discovered that vaporizing the fuel mixture led to higher thermal efficiency, which would produce more power. Its radical hot-steam technology transformed a standard Pontiac Fiero – which produced a geriatric 90 horsepower – into a very nervous 250 hp tuner car.

    Here’s a taste of what Yunick’s vehicle accomplished on the race track

    • Daytona 500 victory (1961, 1962)
    • Indy 500 victory (1960)
    • NASCAR Cup Championship (1951, 1953)
    • 57 NASCAR race wins

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