This Jaguar XJ-S Trans Am car turned a housecat into a race winner

When we hear the words “Trans Am,” most of us think of screaming chickens, Burt Reynolds’ mustache, T-tops, and mullets. For the race fans among us, some different cars may come to mind, like Boss 302 Mustangs or Mark Donohue’s Camaro. In other words, cars that actually raced in the Sports Car Club of America’s famous Trans Am series. Back in its early days in the late ’60s and early ’70s, Trans Am hosted the front lines for the pony car wars; as the rules evolved over the years there were Porsche 911s, Corvettes, Mercury Capris, and Audi Quattros in the winner’s circle. One of the series’ most successful cars, though, was an unlikely hero—the big, heavy, complicated luxury grand tourer that is the Jaguar XJ-S.

An extensively modified XJ-S won the Drivers’ Championship in 1977, and in 1978 an even quicker version of the big cat dominated the series—despite being heavier and having a smaller engine than the horde of competing Corvettes. A fast car that isn’t supposed to be fast is always cool, and the famous 1978 champion is up for auction in Amelia Island this year. One of the winningest Jaguars around, it’s estimated to sell for $200,000—$300,000.

Back in 1976, Jaguar had just discontinued the E-Type, a legendary car that left some gigantic shoes to fill. The E-Type’s replacement, the XJ-S, just didn’t fill them. Sales were disappointing, so Jaguar took to the tried-and-true “win on Sunday, sell on Monday” formula, aka “take your car racing so people will think it’s sporty and want to buy it.” The Trans Am series seemed like a good fit for the XJ-S, and Jaguar approached a private race team called Group 44, which was run by a fellow named Bob Tullius in Virginia, to do most of the dirty work.

Group 44 was a natural choice. A professionally run organization packed with talent, Tullius’s team had already won SCCA National Championships in MGs, Triumphs and, in 1975, a Series III V-12 Jaguar E-Type. Tasked with turning the XJ-S into a winner, Group 44 campaigned one car, painted in the team’s famous green and white Quaker State livery, in the 1977 season. Thanks in large part to Tullius’s consistent, smooth driving, he won the Drivers’ Championship in the Trans Am Category 1 class. With only one XJ-S in the field, though, Jaguar lost out on the manufacturers’ title to Porsche.

In order to keep winning, a new car was necessary. While the ’77 Group 44 XJ-S was extensively modified, it was still largely based on the production XJ-S chassis. For the ’78 season, though, Jaguar and Group 44 developed a more hardcore silhouette racer. Jaguar supplied an acid-dipped lightweight body shell to Group 44, who put it on top of a purpose-built tube-frame chassis. The engine was still Jaguar’s 5.3-liter overhead cam V-12, but it was fed by six Weber carburetors instead of the fuel injection in the road car, and extensively breathed upon to put out 580 horsepower at 8000 rpm—well over twice that of the standard, 244-hp 1976 XJ-S you could buy at the dealership. Massive wheels and Goodyear tires, modified suspension, and a 32-gallon fuel cell rounded out the package.

Despite all the work put into the car and the lessons learned in 1977, the Jag was still up on weight and down on displacement compared to the competition. In this oh-so-’70s short documentary on Group 44, host Brock Yates describes the car as “more like a very fast and stable highway car than a full-blown competition automobile. It’s suspiciously smooth.” Tullius finished in a disappointing ninth place in the season’s first race at Sears Point.

The disappointment didn’t last long, however, as he finished on the podium in the second and third rounds. Then, for the rest of the 1978 season, the checkered flag saw nothing but Jaguar as Tullius won seven races in a row, tying Mark Donohue’s record for most consecutive Trans Am wins. At Road America he clinched the drivers’ championship and at the season’s final round in Mexico City he brought the manufacturers’ title to Jaguar in the Category 1 class (Category 2 was for more extensively-modified race cars like the Porsche 935). Other than a second XJ-S run by Group 44 in a few races, Tullius still had the only Jag in the field, its big V-12 sounding glorious among all the Chevy V-8s and Porsche flat-sixes.

Having beaten everybody with the XJ-S, Group 44 spent the 1979 and 1980 seasons successfully campaigning a Triumph TR8. The team ran an XJ-S again in 1981 and Tullius notched two Trans Am wins and even clocked 194.46 mph at Daytona but did not clinch either championship. Group 44 also helped facilitate Jaguar’s return to top-level international sports car racing with the V-12-powered XJR-5 and XJR-7. Across the Atlantic, meanwhile, Tom Walkinshaw Racing’s XJ-S was a consistent winner in the European Touring Car Championship.

As for the Trans Am-dominating car from 1978, it went into storage for many years before going to a collector in 2007 and has since been mechanically restored, but it reportedly remains largely original cosmetically. RM Sotheby’s, who is offering it in Amelia Island this year, also sold the car in Monterey back in 2013 for $154,000. While there is also a drop-dead gorgeous $6.5–$7.5M Jaguar C-Type from 1952 up for grabs in Amelia Island this year, this XJ-S won more races and even if it isn’t anywhere near as pretty, it arguably sounds better. We’re definitely eager to see what kind of money it brings.

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