At its peak in the late 1980s and early 1990s, the International Motor Sports Association's Grand Touring Prototype machines gave IndyCar absolute fits. The Andrettis were there, Mario and Michael, as were A.J. Foyt and Bobby Rahal and Martin Brundle -- and the fans flocked to it.
IMSA is ready to give Indy another scare starting with this weekend's Rolex 24 At Daytona sports car race with a fresh and electrified take on some of the fastest and most imaginative race cars this country has seen.
Four decades ago, rich with car companies annually pouring tens of millions of dollars apiece into fierce on-track wars, GTP's auto manufacturers brought the downright wildest machines to America's city streets and classic road courses for our vehicular entertainment. Like alien spacecraft that fell to earth, GTP cars looked and sounded different from anything else racing had to offer.
Yes, IndyCar drew more attention with its world-famous Indianapolis 500, and NASCAR's Daytona 500 was an undeniable powerhouse, but if you were looking for a party and loved wickedly combative sports cars, GTP was your jam. And fans duly responded, making IMSA a sporting property that was nearly as popular as IndyCar -- the country's long-held favorite -- and well clear of NASCAR, then a regional delicacy that wasn't quite ready for prime time.
At its heights, GTP gave us Chevrolet versus Porsche versus Nissan versus Mazda versus Toyota versus Jaguar in a 200 mph sports-car cage match. Races played out live on ESPN and in front of packed grandstands as the IMSA GTP tour stretched each season from California to Connecticut. And then, as amazing things often do, GTP couldn't support the weight of its success and came to a crashing end.
For the bigger GTP manufacturers, rising costs to remain competitive became untenable. Before its closure, the factory Nissan GTP team based on the outskirts of Los Angeles employed more people for its IMSA program than the Ferrari, McLaren, and Williams Formula One teams combined. In its era, IMSA was a monster, but along with those soaring budgets required to remain competitive, it was felled by a financial recession that struck at the same time. GTP's lights went out at the end of 1993.
Thankfully, history has an interesting way of reimagining itself.
Thirty years after the original GTP cars went silent, IMSA is ready to relaunch its iconic class with a twist that offers modern relevance to its interested members from the auto industry. It was announced in 2021 that GTP would return with hybrid-powered machines that blend the latest EV battery technologies with purebred internal combustion engines.
All-important styling cues, carried over from the road cars made by GTP's manufacturers, have been transferred to the noses and flanks of the 670-horsepower hybrid prototypes. Given multiple ways to incorporate their showroom ideologies into the hearts and looks of the GTP cars, the response has been phenomenal.
Striking the perfect chord with carmakers, the new GTP formula is loaded with automotive heavyweights to start the fight anew as Honda through its Acura line, BMW, General Motors with its Cadillac brand, and Porsche are ready to race across Saturday and Sunday in pursuit of victory and the promotional bragging rights that come with winning the Rolex 24 At Daytona. Then it's on to 10 more stops on the domestic tour that runs through October, with Cadillac and Porsche making a June detour to France for the 24 Hours of Le Mans.
Their respective GTP models will be joined next year by Lamborghini, and in 2025, McLaren Automotive is expected to bring IMSA's GTP manufacturer tally up to a half dozen. Look across to IndyCar, stuck on two manufacturers for a decade, and NASCAR, with the same three brands it has had for 10 years, and GTP's tech-friendly rulebook has clearly caught the attention of American, German, Japanese, Italian and English marques.
A launch this weekend on the famed Daytona International Speedway roval with the iconic and grueling 24-hour race of survival is where the new-era revival is taking place, and so far, it has the look and feel of GTP's former self.
"It's like the GTP era at the beginning, but we're on the dawn of another golden era for sports car racing," NASCAR and IMSA chairman Jim France, whose father Bill France founded both series, told ESPN. "The teams and drivers competition that we're going to have, it's just fantastic. We've had great racing, but it's been a long time since we've had this many big teams, cars and manufacturers competing at the same time. And if everybody shows up in the next two years that we think will be here, it's going to get bigger."
To France's point, the names involved with today's hybrid GTP cars read like an all-star roster of North America's greatest entrants. Half of the full-time IndyCar team owners are splitting their time with GTP, including IndyCar and Indianapolis Motor Speedway owner Roger Penske with the Porsche Penske Motorsport organization.
Michael Andretti -- who continues to pursue a pathway into F1 with Cadillac -- has partnered his Andretti Autosport team with Wayne Taylor Racing. Mike Shank and Jim Meyer, winners of the 2021 Indianapolis 500 and the last champion in GTP's predecessor, IMSA's DPi class, are participating. So is Chip Ganassi Racing, winners of the Indy 500 last May. And three-time IndyCar champion Bobby Rahal, along with team co-owners David Letterman and Mike Lanigan.
A more meaningful link to France and the 24 Hours of Le Mans, the world's biggest motor race, has also been restored with the revival of GTP. Long before the PGA and LIV Golf were heated rivals, IMSA and the rule makers behind the great endurance event acted like a long-married couple in the throes of a divorce. Le Mans had barred IMSA's DPi cars from participating, but both sides have finally managed to agree on a common set of rules that would allow GTPs to run at the Circuit de la Sarthe and give the FIA World Endurance Championship's equivalent -- its Hypercar prototypes -- the green light to race in IMSA.
Together with IMSA's familiar North American calendar, the newly opened doors to compete for the overall win at Le Mans has been a massive difference-maker for GTP entrants and manufacturers.
"[Cadillac are] interested in all of the races, but certainly when you add Le Mans into the equation, that's something they mentioned in the first two or three sentences of getting together, I can tell you," Ganassi said. "While the eye is on that prize as well, there are plenty of races before that, including [Daytona], that we want to win."
Meyer Shank Racing's Helio Castroneves, the four-time Indy 500 winner, is a veteran of top-tier prototype racing, having competed for Team Penske and Porsche in the 2000s and more recently for Penske where he won the 2019 DPi championship in an Acura and again last season with Meyer Shank in DPi. Count Castroneves among the many who are rooting for the hybrid GTP cars to conjure some of the old GTP magic.
"They still have a combustion engine but the cars are integrating all the new technology, so people are curious," said Castroneves, whose Acura ARX-06 starts from pole position at Daytona. "And the design of the cars ... come on. They are sexy machines. They're incredibly good looking. And they're fast, and that's why I love it. We get to race with the Hypercars if we go over there and they can come to us and race here. I'm telling you: they say this is going to be a golden era, a platinum era, or something great like that, and I truly believe it will. These are amazing times to be in IMSA."
There's a gold rush to compete in GTP with big manufacturers, and in the coming years, the original heyday of GTP might be indistinguishable from its hybrid offspring. Toppling NASCAR on the popularity front isn't realistic, but with all of the energy and manufacturer buy-in surrounding IMSA, IndyCar has a real reason to be concerned.
"The real cherry on the top was with the new rules and all the excitement that's going on with what they're doing with it," Andretti said. "The future of this series looks so, so bright."