The 1960s were a time of innovation and competition in the American automotive industry. Detroit automakers produced some very special factory race cars that were generally unobtainable for most racers as they were rare, expensive, and available only to the most well-known and factory-connected race teams. In this article, we take a look at these race-engineered versions of Chevrolet and Pontiac models from the 1960s that are known as factory lightweight and race car specials and are highly sought after by present-day collectors.
Chevrolet Z11 427 Impala
Chevrolet was one of the originators of combining aircraft type weight reduction techniques together with the addition of a high-performance engine to its full-size models to help drag racers gain an edge on race day and to maximize the Impala’s quarter-mile mojo, they enhanced the lightweight program even more for the 1963 season. The result was a special competition package intended for drag and NASCAR racers, called the Z11, which has become legendary among car buffs and collectors. The package included frontal area aluminum body panels in place of the stamped steel versions, together with non-raised purpose equipment deletions such as sound-ending material, radio, heater, and front anti-sway bar.
The most impressive party trick, though, was beneath the hood. Here, Chevrolet developed a highly modified version of the 409 engine that was bored out to 427 cubic inches and featured a high-rise aluminum intake manifold atop which sat two four-barrel carbs. Also included were forged internal components and a special cowl induction cold air engine intake system. The engine produced 430 horsepower and a staggering 575 pound-feet of torque and could blister through the quarter mile in the low 11-second range.
In total, it is believed that around 50 to 57 Z11 427 Impalas were built, with only seven known to exist today.
Pontiac Swiss Cheese Catalina
Pontiac had its own groove going on in the early 1960s when it came to factory-built drag race cars. In late 1962, Pontiac debuted a lightweight Catalina race special with the Super Duty 421 engine underrated at 405 horsepower and offered these to race teams for the 1963 NHRA race season. Fourteen of these cars were built and included the expected light-weighting measures such as aluminum body panels and non-essential equipment deletion. Incredibly, though, Pontiac dug deep into the crazy bin and came up with an idea that took weight reduction a step further.
They decided to modify the box section frame rails by removing one entire side, leaving a U-shaped channel, and then punching 120 large-diameter holes into the vertical portion of the rails. All the techniques applied saved around 400 pounds over that of a factory stock Catalina with the 421 Super Duty and earned the car the nickname of the Swiss Cheese Catalina.
Nine of the 14 produced Catalina 421 Super Duty lightweight still survive today and are highly treasured on the car show and auction circuits, thanks to their intriguing construction and racing provenance.
Pontiac Tempest 421 Super Duty
In early 1962, two race teams brought modified Pontiac Tempests to the NHRA Winter Nationals that they had stuffed race-spec 421 Super Duties into and replaced the stock transaxle driveline with a conventional manual transmission and differential from a Catalina. It seemed to do the trick as the Tempests were a half a second quicker through the traps than the next quickest cars in their class. Engineers at Pontiac took notice of the team’s Tempest victories, inspiring them to create their own factory versions of the 421 Super Duty Tempests for the 1963 race season.
They built 14 of the combat-ready Tempests consisting of a mix of eight coupes and six station wagons. Yup, that’s correct, station wagons! For these cars, the steel front-end body panels were swapped out for aluminum versions, and the car’s original 326 cubic inch engine replaced by the underrated 405 horsepower 421 Super Duty with dual quad carburetors, forged internal components, and tubular stainless steel headers with 3-inch diameter outlets. All 14 of the white painted Tempests were built over a two-week period in December of 1962 and wore 326 engine identifier badges as sort of an inside joke for the race crowd.
The cars could tame the quarter-mile in the low 12-second range with some tuning, and high 11-second times with the rear transaxle driveline swapped out for a conventional manual transmission and differential combo.
Corvette Grand Sport
Not all of the factory lightweights from GM in the early 1960s were meant for the drag strip. The Corvette was completely restyled for the 1963 model year and received improved powertrains and handling attributes. The updated car now had the potential to be competitive against the Shelby Cobras, Ferraris, and Porsches on road race courses. Help was needed, though, and in stepped Zora Arkus-Duntov, the director of high-performance vehicles at Chevrolet, to infuse some road racing mojo into the Corvette by creating the 1963 Corvette Grand Sport.
The Grand Sport was a lightweight version of the 1963 model featuring an aluminum-block, 377-cubic-inch V8 engine that developed more than 550 horsepower and was intended to compete in the 1963 Le Mans race. They raced during the Nassau Speed Week and were competitive and slammed the Shelby Cobras but failed to take first place in the Trophy race, the final event of the series.
In 1964, Roger Penske returned to Nassau and took the checkered flag at the Trophy race. These cars were bad to the bone and an indication of the direction the Corvette was heading if factory-directed race development efforts were permitted to progress. Zora applied a litany of weight-saving measures to make this car a bare-bones, purpose-built race warrior that resulted in a 1,300-pound weight reduction over that of a stock Corvette Stingray’s 3,200-pound curb weight.
All five of the original Corvette Grand Sports still exist and occasionally pop up at auto shows and other events. Rarely, one of these will appear at auction and command prices of over 5 million dollars.
These are some great cars that Chevrolet and Pontiac produced for racetrack battle and a great peek into the light-weighting and powertrain technology that GM had developed or adopted in the 1960s. Interestingly, four of the five cars featured in this video were from the year 1963, and it’s not a coincidence. In late 1962, things were getting wild in the Pontiac and Chevrolet factory performance departments as this was just before the time when GM management became serious about enforcing an agreement that was entered into in 1957 by Ford, Chrysler, and GM that declared each of the manufacturers would not engage in the development and building of factory-backed race cars.
The Chevrolet and Pontiac performance groups responsible for developing the lightweight race cars knew that the enforcement was forthcoming in late 1962 and expedited production and delivery of the 1963 model year cars to dealerships and race teams before the band date. Before orders by GM leadership came down to destroy the cars.
Conclusion
These forgotten 1960s Chevrolet and Pontiac factory race cars were incredibly rare, expensive, and available only to the most well-known and factory-connected race teams. However, their legacy lives on today as highly sought-after collectibles by car buffs and collectors.
With their advanced lightweight technology and high-performance engines, these cars were ahead of their time and paved the way for future developments in automotive racing. They are a reminder of a bygone era when automakers took racing seriously and pushed the limits of what was possible on the track.