cadillac hybrid prototype
The noiseless, all-electric launch is disconcerting in isolation from the frenzy of competition.
Marc Urbano

Like all its IMSA GTP competitors, the new Cadillac hybrid prototype leaves its pit box on pure electric power. If you’re not watching closely, you could easily miss its exit. It leaves only a rising electrical golf-cart hum and a bit of kicked-up dust in its wake. For those who’ve heard the deep bellow of earlier American Le Mans efforts—such as the Ford GT40 Mk II, the Corvette C6.R, and the Viper GTS-R—the Caddy’s departure disappoints.

This story originally appeared in Volume 16 of Road & Track.

But when it reaches the fast lane, hell breaks loose. Fired by a Bosch motor-generator in the transmission’s bell housing, the factory-designed and -built 5.5-liter V-8 instantly overtakes the aural landscape. Its volume overwhelms nearby microphones, and the suddenness with which that wall of sound hits widens eyes and causes heads to snap to attention. It is, in a word, spectacular.

cadillac hybrid prototype
Any bug that hits a Cadillac LMDh’s nose dies a glorious death. Per LMDh rules, the Cadillac shares its hybrid system and transmission with its competitors.
Marc Urbano

All the other entries in IMSA’s reconstituted GTP class—each using an identical battery, motor-generator, and transmission to the Cadillac’s—also depart their pit boxes on pure electric power, even though it isn’t mandated. But the Cadillac is the only one with a naturally aspirated engine in the class. And only Cadillac understands the full power of the start-up drama.

The company has some practice in this area. Ask anyone whose neighbor owns an Escalade V. Its start-up exhaust note is absurdly loud. Obnoxiously loud. Awesomely loud. It’s no coincidence. If this Cadillac prototype racing effort is to spread the V-series gospel (at amplified volumes), it needs to share some ties with production cars. And since street Cadillacs don’t go trundling around strip-mall parking lots on full carbon- fiber platforms constructed in Italy by Dallara, the exhaust note is one of the few connections. It’s why this new engine is a cross-plane unit instead of a flat-plane, as in the Corvette race car. It shares at least a basic deep-throated character with the V-series street cars, if no actual parts.

cadillac hybrid prototype
Coupe de Badass.
Spencer Lowell

Just in case there’s any doubt about the racing effort’s connection to the carmaker, Cadillac’s executive chief engineer, Brandon Vivian, is here to set the record straight. “We own the cars. We choose the drivers. We designed the engine. We built the engine. It’s ours,” he states emphatically.

And what an effort it is. According to Adam Trojanek, the lead propulsion engineer, General Motors started work on the engine in mid-2021. The V-8 made it to the dyno in March 2022. Unlike recent Cadillac prototype engines—pushrod units often built by third parties—GM Powertrain constructed this DOHC engine in Pontiac, Michigan.

cadillac hybrid prototype
Beauty is only skin deep, and that’s a helluva skin.
Spencer Lowell

Cadillac lined up megateam Chip Ganassi Racing more than two years ago. Ganassi ran two seasons in IMSA with the previous Cadillac proto­type in preparation for this year’s Le Mans run. Cadillac signed the drivers, including experienced Cadillac pilots Sébastien Bourdais, Renger van der Zande, and Pipo Derani, as well as Indy superstar Scott Dixon for endurance-race help and newcomer Alexander Sims. Curiously, there’s not an American among them.

In addition to Ganassi, Cadillac has a second team. Longtime associate Action Express Racing of Charlotte—owned by Jim France, CEO of NASCAR—will run a car in IMSA for the full season. Under Cadillac’s direction, Action Express and Ganassi, two former competitors, share data and resources. A third car will run in the FIA World Endurance Championship (WEC), which counts Le Mans as a round in its season. Ganassi will run it through a shop in Stuttgart, Germany. This is a big program. But when the ultimate goal is to beat Ferrari, Porsche, Toyota, and Peugeot at the 24 Hours of Le Mans, a small program won’t cut it. Cadillac is the only one on that list that hasn’t won at Le Mans. Porsche has 19 wins.

cadillac hybrid prototype
Muscle moves machines. But just finding a good push spot is wicked tough.
Spencer Lowell

But worries about besting Porsche, Ferrari, and the others must wait. When I visited Chip Ganassi Racing just before Christmas 2022, the thing that terrified the team was the 46-pound, German-­built Bosch motor-generator and the tiny, cockpit-­mounted 1.35-kWh battery from Williams. Without those pieces, a car built to the IMSA GTP rule set cannot run. The motor and the battery that powers it add to the propulsion system a relatively meager 40 to 67 hp, depending on the track, and also act as the engine’s starter and alternator. If the system packs up, the car is done. Mike O’Gara, who is in charge of the Cadillac program at Ganassi Racing (and who ran the Ford GT program that took a Le Mans class win in 2016), is nervous. “We’re control freaks here,” O’Gara says, “so everything we can control, we do. Having something like this hybrid system that’s critical to the running of the car be out of our control is really foreign to us. And even if the supply was fine and the reliability was good, just having something out of our control is uncomfortable.”

He’s not alone: Everyone else in Chip Ganassi Racing’s 105,000-square-foot HQ in Indianapolis was nervous too. So was everyone on the Cadillac corporate side. In fact, everyone involved in the GTP class was terrified. The first race of the GTP era, the grueling Rolex 24 at Daytona, loomed over the holiday season, and there were dark predictions that—gasp!—an LMP2 car would win overall. The hybrid elements took longer to get to teams than expected. It pushed Cadillac and every other GTP effort back by several months. They weren’t ready. Nobody was ready. They didn’t know if they’d even have the spares of the spec parts should something fail. And how could they not fail?

cadillac hybrid prototype
Bodywork shows off how densely packed this Cadillac is.
Spencer Lowell

But by the close of the 24 Hours of Daytona in late January, it was clear that the GTP cars hadn’t failed. BMW and Porsche had serious issues with the hybrid components during Daytona. But Cadillac didn’t. Neither did Acura. Still, star driver Bourdais is sullen. He just finished his last stint in the yellow-­nosed Cadillac with an hour and 40 minutes left in the race, and he knows Cadillac can’t win on speed. “I don’t understand it,” he says, staring off. He couldn’t catch the leading Acura ARX-06s.

And so it went. Cadillac only managed spots three through five, behind both Acuras. Jamie Coates, Ganassi’s team manager for the Cadillac effort, moved purposefully through the pit box after the checkered flag flew, hugging every crew member. His glassy eyes spoke to the program’s emotional and physical toll.

cadillac hybrid prototype
Carbon fiber and engineering necessity can produce something sculptural. Speed is expressed as streaks.
Marc Urbano

The Acuras won’t be at Le Mans, at least not in 2023, so Cadillac needn’t worry about them. But there will be plenty of battle-tested entries. And they’ve spent multiples of the number Cadillac has.

The only French thing about Cadillac is the derivation of its name. And since Antoine de la Mothe Cadillac died 172 years before the car company was founded, that connection is pretty meaningless. Yet Cadillac, which sells basically zero cars in Europe, has sustained an interest in the French enduro rivaled only by Ford among U.S. automakers. In part, the brand’s interest is about nostalgia, the power of Le Mans past. When Briggs Cunningham wanted to make an honest run at the French classic in 1950, he took Cadillacs. Well, it was the Cadillac V-8s he wanted. He planned to bolt them into Ford bodies until the Le Mans organizers objected. Instead, he entered a stock-looking Series 61 and the Cadillac-­powered, massive (and massively weird) “Le Monstre” aerodynamic special, finishing 10th and 11th, respectively. By all accounts, the fans adored Cunningham’s big, outrageous Cadillacs.

cadillac hybrid prototype
A day of racing at Daytona produces filthy awesomeness along the Caddy’s flanks. Any night spent racing is exhausting.
Marc Urbano

Fifty years later, Cadillac mounted an ill-fated run at the overall win with the factory-backed Northstar LMP program. The first Northstar LMP, based on a five-year-old Riley & Scott chassis, embarrassed itself at the great race in 2000. It was 6.5 seconds slower than the pole-winning Audi in qualifying. The best of the four Cadillacs finished 19th. Despite significant changes to the car over the next two years, the program never recovered from its dismal start. Its best finish at Le Mans was ninth. Cadillac pulled the plug in August 2002. By the company’s own admission, it had badly underestimated the competition at Le Mans and had consequently committed too little money and technology to the program.

Now, with a stable rules package and an adjustable balance of performance between disparate car types within the same top class, Cadillac should at least be on an even footing with the others at the centenary race at Le Mans. It’s already won the best-sounding car in the prototype class. Now it just needs to do those other things.

Update: Cadillac might not have won the Rolex 24 at Daytona, but it did win the next race, the grueling 12 Hours of Sebring. Sure, the Action Express Cadillac V-Series.R won because the top three GTP-class cars ahead of it knocked each other out in a single accident just 20 minutes from the end. But a win is a win. And so far, it’s the only win, in either IMSA or WEC competition, for the Caddy in the run-up to Le Mans. In WEC races, where Toyota has dominated, the Cadillac scored two 4th places and a 5th. The car’s generally excellent reliability bodes well for Le Mans.

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Daniel Pund
Executive Editor

Daniel Pund is a veteran car reviewer, feature writer, and occasional bomb thrower.