From efficiency to airflow, it’s a golden age for racing tech in our driveways

Why do car companies go racing? First and foremost, they do it for marketing. Almost as soon as the first cars turned a wheel, they were being raced against each other to show the world—and all those potential customers—who built the fastest and most reliable motor car. Bob Tasca, a Ford dealer and leading figure in drag racing, articulated it best. “Win on Sunday, sell on Monday.”

Whether that still holds true 50 years later in an age of far greater competition for our interest isn’t clear, but today salesmanship certainly isn’t the only reason to race. Take another quote, this time from Soichiro Honda, founder of the Japanese auto giant that bears his name: “Racing improves the breed.”

Considering the source, maybe that’s just post-hoc marketing justification. Or… perhaps racing really makes our cars, our day-to-day vehicles, better.

The Goldilocks zone

If you want to actually win on Sunday, you have to design, engineer, and build a car that’s better—for the given set of rules—than everybody else who turns up. And in the course of doing that you can learn or test things that can improve the cars you sell, particularly if the rulebook encourages this kind of innovation. Not every racing series does this, however. In some cases, the cars must be so specialized for the task in hand that any lessons learned aren’t transferable. There’s not much on a Formula 1 car, for instance, that’s relevant to what we drive on the road. Other times, the rules are so tightly controlled that much of the equipment is identical across competitors, leaving less to be learned. Every IndyCar IR12 on the grid uses the same chassis, NASCAR Generation 6 stock cars all use an identical chassis, and the same is true for the German (DTM), Australian (V8 Supercars), and Japanese (Super GT) equivalents.

This insistence on standardized parts often stems from a goal to keep costs in check. When car companies go racing, the desire to win sometimes manifests as a willingness to open one’s wallet more than the next factory. But big racing budgets are less justifiable to shareholders or a board of directors when they don’t bring results on track, and each race only has a single victor. And more than one racing series has found out the hard way that a spending arms race can make for bad entertainment if one team becomes especially dominant. Races where the results are a foregone conclusion just aren’t as exciting for the fans to watch, and previously diverse pools of competitors soon evaporate.

The Corvette Z06 street car…

Eric Bangeman

The Corvette Z06 street car… Eric Bangeman

And its close relative, the Corvette C7.R race car.

Eric Bangeman

And its close relative, the Corvette C7.R race car. Eric Bangeman

The Corvette Z06 street car… Eric Bangeman

And its close relative, the Corvette C7.R race car. Eric Bangeman

However, rulebooks can be written that hit a sweet spot—overlapping sets on a Venn diagram where there’s room to innovate but not so much that everyone else gives up and goes home. Under such circumstances, technologies can be developed with real-world relevance. Since the turn of the century, one rulebook more than any other exists in this Goldilocks zone, and it’s being used to good effect in series like the Tudor United SportsCar Championship (TUSC) and the World Endurance Championship (WEC). Automakers are spending tens and even hundreds of millions of dollars on racing programs, often paying for it from R&D budgets as well as (the more traditional) marketing.

The results have been showing up in road cars generally as more power, greater efficiency, and improved reliability, leading to what is arguably a current golden age for road-relevant technology transferring from track to street. That’s a view shared by John Hindaugh, a broadcaster and commentator with a long background in the sport. Hindaugh is the voice of Radio Le Mans (you may also recognize him from commercials for both Forza and Gran Turismo), and he’s been watching this era evolve right before him. “In pure engineering terms, making that technology transfer has always been difficult. You could argue it’s been a long time since anything useful directly has come from a race car to a road car.” But, he told us, “it’s been an amazing turnaround over the last 15 to 16 years.”

Hindaugh in particular noted the resurgence of endurance racing as a big instigator in modern tech transfer. “It’s the development in pursuit of efficiency as well as power,” he said. “The guys at Le Mans did as many laps as last year, at the same speeds, but with 25 percent less fuel! In motor racing we want to be fast and exciting, but bringing in the efficiency has made people think differently.”

Audi has certainly led the way in this department since 1999, and Hindaugh credits them for taking a leap of faith. “They were the first people to transfer the technology that they had into road cars when the cars they were racing didn’t look like road cars,” he said. “[Audi] have developed things like TFSI [direct injection] to get that virtuous triangle of power, reliability, and efficiency. Normally you can only get two out of three.” Audi develops its racing engines and road car engines at the same site in Neckarsulm, Germany, and the company credits the atmosphere and culture of this combined workplace. Engineers in different programs can congregate over the coffee machine, making technology transfers an organic process.

There are different classes of cars that race (at the same time, on the same track) at Le Mans and its associated series. Audi has been competing in the fastest class, an area typically reserved for purpose-built prototypes that visually bear little resemblance to something we could buy from a showroom. Others choose to campaign what are known as GTs, racing cars that begin life as production road cars. This group includes the likes of Chevrolet, which has had a great deal of success since 1999 with its Corvette Racing team.

Practical lessons?

The team prepares the #4 Corvette Racing C7.R race car for a Tudor United SportsCar race at the Circuit of the Americas in Texas.

Credit: Jonathan Gitlin

Let’s take a look at Chevrolet’s new Corvette Stingray, the C7, as a case study. The company’s current factory racing program started with a previous generation Stingray, the C5. According to Harlan Charles, the car’s Product Manager, that program has taught Chevrolet much over the years. “Early, from the fifth to sixth generation, we went to high-intensity fixed headlamps from popups. Then we moved to cooling,” he told Ars. “The Corvettes through the ’80s and ’90s were mostly worried about drag, which is important for racing, but the lift was important, too. And the bottom breathers we were doing at the time—it wasn’t the best thing for lift.”

Charles is referring to the way the C5 Corvette fed its radiators with cold air drawn in from underneath the engine bay. Sucking air up into a car’s engine bay from underneath means the front end is constantly experiencing lift, which is exactly what you don’t want to happen, particularly on track. “We had to convert it and start opening up grills in the race car,” Charles said. Today whenever you see a racing Corvette in the flesh‚ or rather carbon fiber, you can’t help being struck by all the grills and scoops that move air into and out of the car. And you get the same feeling with the newest-generation road car (the C7), particularly if it’s equipped with the Z51 pack as a recent test car supplied to Ars was.

“We learned from that and applied it to the sixth-generation car, and what we learned from that has gone into the seventh. We have the cooling vents on the hood, on the quarter, and now with the new Z06 we’ve worked closely with the race team,” Charles said. The goal has been to increase downforce—the opposite aerodynamic force to lift, where air pressure pushes the car down and helps keep the tires in as much contact with the road surface as possible. “Most street cars don’t have downforce. The new Z06 is the first downforce car we’ve done from the factory. Ground effects, a larger wing, and front splitter,” he explained.

Jim Campbell, vice president for Performance Vehicles and Motorsport at GM, echoed this.

“Our goal in every series we race in is to optimize how much tech transfer we can drive into the vehicle or the powertrain of the production vehicle. The C6 had a vertical radiator. It brought air in the lower air intake, drove it through the radiator, and exited the hot air underneath the vehicle. In racing we angle the radiator and have a hood extractor which is an efficient way to get hot air out of the radiator. You decrease lift, increase downforce. It makes a difference. We learn a tremendous amount about all aspects of the race car, so we can transfer over the true technology. The way we do thermal management—cooling engine, the brakes, the whole system, that’s a big one. The aerodynamic learning is significant.”

GM’s Jim Campbell explains to Ars what the company gets from racing.

Credit: Elle Cayabyab Gitlin

Making downforce from hot air exiting the engine bay is a good thing, unless that hot air slowly cooks anything behind it. In this case, that means the bit where people sit. Drivers of the last-generation Corvette could get pretty warm, especially if they were driving a convertible and not moving that fast. The newest Stingray manages this waste heat much better in our experience, failing to roast its driver even in the height of a Washington, DC, summer. The optional seats fitted to our test car learned another trick from the race car: blowing cool air through them. TUSC and WEC racing both require cars to have air conditioning to keep cockpit temperatures within safe levels, and Corvette Racing’s AC system blows cold air into the driver’s helmet and through their seat.

Charles pointed to weight as another specific example of the race car transferring technology to the new C7. “The ’04 Z06 was the first mass-produced carbon fiber part on a (relatively) high volume car, and now on the seventh generation we have a carbon fiber hood, roof—every car has that standard,” he said. “We went from steel frames to aluminum frames.” This switch required Pratt and Miller (the engineering company that runs the racing team) to develop a new way to bond a steel roll cage to the frame, since just welding steel and aluminum together can lead to galvanic corrosion (something that the Navy seemed to forget recently). Other race-proven tweaks in the name of weight include dry sump oil systems and relocating the battery to the rear of the car for better distribution.

A less obvious example of borrowing from the track, according to Charles, is the Corvette’s optional data recorder. This combines a camera and microphone with data pulled from the car’s sensors, similar to the aftermarket data acquisition system we use when racing. In this case it’s a factory option, one that needed an update when it was pointed out that the valet mode, which records what happens when you give someone else your keys to park the car, might not be entirely legal in some states.

Charles said he and his team were proud of the similarities between the race and street cars. “If people are buying these cars, the ultimate testament to the car is how it does at Le Mans, how it does in TUSC; a lot of people use that as a gauge of the technology. We’re really competing against the best in the world; most of our competitors are European sports cars and we’re very proud that we can go up against them,” he said.

This sort of thing happens throughout the racing paddock. Dodge’s Viper is a home-grown rival to the Corvette, and until the end of 2014 it could be found racing hard in the Tudor series. Russ Ruedisueli, director of the Viper motorsport program, pointed to chassis-stiffening and engine lubrication improvements when we asked what lessons SRT had learned racing. He also cited a move to carbon fiber for the car’s hood, roof, and deck-lid assemblies.

Some tech improvements from the track are still waiting to make this translational leap. For example, both Corvette and Viper race cars use rear-mounted cameras and radar sensors to keep the driver aware of what’s behind them. As fast as they are, the prototypes are even faster, and too frequently we’ve seen accidents at Le Mans and elsewhere as those prototypes try making their way through traffic. These systems can discriminate between different cars (so you don’t move over for a rival by accident), overlaying that data onto screens that replace a traditional mirror. Unfortunately, such systems are currently not street-legal thanks to regulations which ban showing a driver an active video display if the car is in forward motion.

The rear of the C7.R race car. There are a lot of vents and holes here to cool the various bits under the skin.

The rear of the C7.R race car. There are a lot of vents and holes here to cool the various bits under the skin.

A Corvette C7.R’s rear view camera, mounted in a rear cooling vent. Behind the fan is the transaxle gearbox.

Jonathan Gitlin

A Corvette C7.R’s rear view camera, mounted in a rear cooling vent. Behind the fan is the transaxle gearbox. Jonathan Gitlin

A trio of racing Vipers. The white one in the foreground is much closer to the street car than the two red machines.

Jonathan Gitlin

A trio of racing Vipers. The white one in the foreground is much closer to the street car than the two red machines. Jonathan Gitlin

A Corvette C7.R’s rear view camera, mounted in a rear cooling vent. Behind the fan is the transaxle gearbox. Jonathan Gitlin

A trio of racing Vipers. The white one in the foreground is much closer to the street car than the two red machines. Jonathan Gitlin

While we’ve been focusing on Chevrolet and Dodge types, it’s not just the big car companies learning how to improve their products. The same Michelin engineer who spends his weekends working with Corvette Racing has also been responsible for developing the bespoke Michelin road tires on the Corvette Stingray. We haven’t had an opportunity to try them (or the car) on a closed circuit yet, but seven days and several hundred miles of exposure to the car left us impressed with their grip in the dry—with enough adjustability to get the rear tires involved in the process of cornering—and the wet, never giving the impression we might be in danger of running out of talent. And yet, these Michelin tires are actually narrower than the tires fitted to the previous generation car.

“Technology isn’t just engines and brakes,” Hindaugh reminded us. “It’s what allows people to make those leaps in tolerances, which are much tighter in street cars than they used to be because people like Mobil have developed synthetic lubricants not just for engines but gearboxes and so on.” This trend is responsible for the ever-increasing service intervals of modern engines (Porsche claims 20,000 miles between oil changes, for example). It’s something that would be unheard of a couple of decades ago.

Teachable moments

Automakers can also use racing to improve our road cars in less concrete, more ephemeral ways. We heard repeatedly in the paddock about the clear benefit derived from rotating production vehicle engineers through a factory’s racing team. GM’s Campbell told us it hones both engineering and leadership skills. “Racing is a fast learning process, we have what we call race time, where you have to move fast with high quality,” he said. “The green flag drops every seven to fourteen days whether you’re ready or not, and we love that spirit and taking that spirit of race time pace back into our vehicle teams and powertrain teams.”

Viper’s Ruedisueli told us something similar. “The other area I’m most excited about is training people,” he said. “Having a racing team and being able to bring people in and be involved in that is a great draw for talent for my group, and it’s also an outstanding place to teach engineers about timetables and solving problems quickly. The example I give is: you can’t show up to Daytona and say ‘can you hold the race an hour because we’re not ready?’ It makes you think a lot differently, solve problems a lot quicker, and come up with creative solutions to make it onto the grid.”