DAYTONA BEACH, Fla. — Cadillac Whelen gave its competitors in the Grand Touring Prototype class of the IMSA WeatherTech SportsCar Championship a sneak preview of its excellent 2026 season in the final two races of 2025.
Jack Aitken, Earl Bamber, and Frederik Vesti drove the No. 31 Cadillac V-Series.R to victories in the TireRack.com Battle on the Bricks at Indianapolis Motor Speedway and the Motul Petit Le Mans at Michelin Raceway Road Atlanta to close out the ’25 campaign. They were the only podium finishes from an oft-frustrating year in which Aitken still finished second in the driver standings.
That strong form carried into the new year with the upgraded ‘Evo’ version of the Cadillac V-Series.R with its distinctive lower mounting of the rear wing. The No. 31 Whelen car claimed back-to-back race wins at the Chevrolet Detroit Sports Car Classic and the Sahlen’s Six Hours of The Glen at Watkins Glen International and five other podium finishes.
When the points were tallied, Aitken topped Laurin Heinrich for the GTP driver championship, Cadillac earned its fifth top-class IMSA manufacturer championship, and Action Express Racing (which administrates the Cadillac Whelen program) took home its seventh team championship – the last four in partnership with Cadillac.
“What a tremendous result for Cadillac Racing and everyone at General Motors,” said Mark Reuss, President, General Motors. “Winning the 2026 manufacturer, team and driver championships is an extraordinary accomplishment and a testament to the strength of this entire program.”
Aitken set the tone for the campaign by turning the fastest qualifying lap for the Rolex 24 At Daytona, only for the No. 31 to be put to the back of the GTP grid for a skid block wear ride height infraction.
The race netted second place after a ferocious late-race duel between Aitken and Felipe Nasr. Nasr shared the No. 7 Porsche Penske Motorsport Porsche 963 with Julien Andlauer and GTP debutant Heinrich, whose 2024 Grand Touring Daytona (GTD) PRO championship at age 23 for AO Racing made him the youngest Pro category champion in IMSA history.
Porsche then scored a 1-2 finish at the Mobil 1 Twelve Hours of Sebring, although it came with a side of different post-race opinions in post-race press conference after Nasr’s No. 7 car beat an unhappy Kevin Estre in the No. 6 car.
Nonetheless, it marked PPM’s second consecutive sweep of the unofficial “36 Hours of Florida” comprising the classic Daytona and Sebring endurance races.
The No. 31 Cadillac finished fourth on the road at Sebring after starting on pole but was elevated to the podium in third when the No. 10 car was penalized for a technical infraction.
At the Acura Grand Prix of Long Beach, Aitken qualified fourth and finished second with Vesti, deputizing for Bamber with a schedule conflict. But the overall victory was delivered by Nick Yelloly and Renger van der Zande in the home race for Honda, Acura, and Honda Racing Corporation USA in the No. 93 Acura Meyer Shank Racing w/Curb Agajanian Acura ARX-06.
At this stage, Nasr and Andlauer led Heinrich (who made his first appearance in the No. 5 JDC-Miller MotorSports Porsche 963 at Long Beach, finishing sixth) by 35 points, with Aitken behind by 38 points.
Heinrich then wrote worldwide sports car racing’s feel-good story of 2026 by teaming with Tijmen van der Helm in the JDC-Miller Porsche (the only private entrant competing in GTP) to grab a sensational victory at WeatherTech Raceway Laguna Seca in the StubHub Monterey SportsCar Championship. On the same weekend that Alex Zanardi passed away, Heinrich evoked memories of the Italian racer’s legendary 1996 last-lap pass for the IndyCar win at Laguna Seca’s Corkscrew with his own late-race heroics to steal the victory from a crestfallen Bamber.
The result lifted Heinrich into the lead of the GTP driver standings (by 21 points over Aitken) and motivated Porsche to adjust its international driver rosters to craft a full-season IMSA GTP program for the rising star after he started the season with only a three-race commitment.
Aitken vaulted into the points lead after he and Bamber took their first win of the year Detroit, but Heinrich’s subsequent appearances in the JDC-Miller car maintained his position as the strongest championship competitor over the second half of the season.
Aitken called Cadillac’s maiden Detroit victory the most memorable and important of his championship campaign. Bamber set the table by claiming the Motul Pole Award in his only qualifying performance of the season.
“I think the home win at Detroit was a bit of a watershed moment for us,” Aitken said. “We had a few near misses early on in the season. We were happy with what we were doing, but we’re racers…not being on the top step is a bit grating. Giving reasons why we were still happy – but would be a bit happier if we would have been on the top step – was also getting a bit old. To finally get the win at home with friends and family all around at the home of GM was a pretty awesome weekend, I think it’s fair to say.”
Rejoined by Vesti, Bamber and Aitken doubled up by winning the next round at Watkins Glen. It was a GTP-era record-setting eighth consecutive podium finish for the No. 31 Cadillac, and it pushed Aitken’s lead out to a season-high 203 points over Heinrich. Still, the young German generated headlines by notching another podium finish in the privateer JDC-Miller Porsche to remain Aitken’s closest championship pursuer.
The plot thickened at the Motul SportsCar Endurance Grand Prix at Road America, which was lengthened into a six-hour round of the IMSA Michelin Endurance Cup for 2026. Contact between Aitken and Estre in the Nos. 31 and 6 cars occurred going into the fast Turn 1 with roughly 10 minutes remaining.
The incident moved Heinrich (who finished second in the No. 5 JDC-Miller Porsche with van der Helm and Kaylen Frederick) within 118 points of Aitken. Filipe Albuquerque and Ricky Taylor claimed the lone win of the season for Cadillac Wayne Taylor Racing and the No. 10 Cadillac V-Series.R.
Porsche’s commitment to backing Heinrich’s championship effort was demonstrated when Laurens Vanthoor stepped aside to permit Heinrich to join Estre in the No. 6 Porsche Penske Motorsport car for the 2-hour, 40-minute sprint round at Indianapolis.
Despite finishing third, Heinrich lost ground to Aitken, who gained nine points in qualifying and finished second to give him an almost unbeatable 147-point cushion heading into the season finale. BMW M Team WRT earned its first IMSA victory courtesy of Dries Vanthoor and Sheldon van der Linde in the No. 24 BMW M Hybrid V8.
Aitken gained another four points in Petit Le Mans qualifying, meaning all he needed to do to clinch the driver championship was roll off the grid. He admitted that such a normally mundane task was worrisome on this day, the pressure intensified by a heavy pre-race shower.
“The start of the day was a bit more stressful than usual and the recon lap was very steady,” he chuckled. “I usually have unwavering faith in the EV launch on the Cadillac V-Series.R. I was really praying that it didn’t let me down this one time, and it didn’t.
“Yeah, a bit of a weird feeling winning a championship rolling to the green.”
Even with the championship already decided, Petit Le Mans provided all the drama it is famous for. Laurens Vanthoor, back in the No. 6 Porsche, passed Bamber in the No. 31 Cadillac for the lead with 48 minutes remaining, then held off a hard charging van der Linde in the No. 24 BMW to share in Estre’s first win in IMSA competition.
Meanwhile, the season ended with a whimper for both championship competitors; the No. 31 Cadillac finished seventh, one place ahead of the No. 7 Porsche, in which Nasr suffered a hard crash with an hour and a half to go while fighting with the No. 6 PPM car for the lead. Back in the No. 7 for the season finale, the eighth-place finish left Heinrich 161 points behind Aitken in the final reckoning.
“It’s a somewhat sad ending to a great season, but I am proud of our victories,” said Heinrich, who has been confirmed for the full 2027 season with Porsche Penske Motorsport.
In the final analysis, the No. 31 Cadillac was simply the class of the GTP field in 2026. The momentum that Cadillac Whelen ended the ’25 season with, combined with the effective Evo upgrades on the Cadillac V-Series.R made for an unbeatable combination.
“In a way, we surprised ourselves at this time last year by finishing second (in the championship) with such a strong end to the year with our back-to-back wins in Indy and here,” Aitken said. “I think it sort of showed us we were ready as a team to go on a streak like we have done. The pieces have been in place for a long time, but we needed a little bit of luck and things to fall in place to really get going with results on paper. That’s how it is in racing always.
“As we went through the first races of the year, had a few near misses in terms of winning,” he continued. “But we were always there, always on the podium, fighting with the top guys, whoever they were. It became clear pretty quick that we were on to something pretty special this year, but I don’t think we expected it to go quite as long as it did.
“It does feel a little bit bittersweet that Earl couldn’t be with me (atop the driver championship standings) because, honestly, he should,” Aitken added. “Missing that one race [Long Beach] doesn’t really mean anything to me. He should be right up here. That’s a shame.”
