Related: Digital Domain
“You can’t stop manufacturers from spending more money, all you can do is make it less and less worthwhile for them to do so,” says Peter Wright, technical advisor for the Federation Internationale de l’Automobile (FIA), the governing body of international motorsport. The balance of money spent–some Formula One teams reportedly are spending nearly half a billion dollars per year, with most dropping more than $150 million each year–entertainment value and sport is a constant problem for racing and the sanctioning bodies that control it. It’s also a problem for the manufacturers competing in the series.
Take the near-constant wind tunnel testing that takes place in an aerodynamically constrained series like F1. Is it necessary? “All of the real work is going on inside of computers these days,” Wright says, “so things like the round-the-clock wind tunnel work tends to be checking the CFD [computational fluid dynamics] models and looking at the interactions it isn’t particularly good at.” In short, it is a lot of money chasing very little gain. The same is true of engine development.
“Cosworth spent about $20 million to design and develop its new grand prix engine, while certain other teams spent upwards of $200 million on theirs,” he says. Judging from pre-season testing and early season performance, the small independent engine maker from Northampton, England produced the best engine for the least amount of money. And that means the $180-million difference was effectively wasted. “That’s a lot of money–shareholder money–and you have to ask yourself what that difference is being spent on and whether anyone realizes this is taking place.” According to Wright, an increasing number of company CFOs are starting to understand and ask questions. Heretofore, the heads of the racing programs and the engineers had been enjoying themselves.
As a result, teams think nothing of carving an engine from billet–an exercise that gives a very precise wall thickness, stable material properties, and that can run non-stop–or having a bill of materials of $250,000 per engine. “In the end, however,” Wright cautions, “there is so little in it that is in common with a road vehicle that it has no real value to the manufacturer.” Or, for that matter, to the customer who buys the cars that are sold under a banner of “race-proven” technical innovation.
Certainly Renault, winner of the 2005 driver’s and manufacturer’s world championships, has discovered the limitations of its motorsports involvement. Despite a crushing performance that relegated most of its competition to also rans, broke the five-year domination of both Michael Schumacher and Ferrari, and gave Spaniard Fernando Alonso the title of youngest F1 champion ever, Renault sales stayed flat or declined slightly in markets around the world–including Spain. This disconnect has caused Renault CEO Carlos Ghosn to call for a review of the company’s Formula One commitment on a year-to-year basis. And while competing successfully inevitably says something–though exactly what is unclear–about an automaker’s ability to battle with the best in the business, “The marketing departments aren’t interested in anything they don’t already have in their product lineup. Suggest that they may have hydrogen-powered hybrids in 10 years,” says Wright wryly, “and they’ll say: ‘Hold on. I can’t think that far ahead.’”
The FIA, however, can. Over the longer term, it’s expected that the FIA will propose an engine formula that limits the amount of air and fuel in an attempt to increase efficiency. It is a technology the FIA believes is of interest to manufacturers, politicians–who might take a jaundiced view of racing if a major fuel crisis hits–spectators, and consumers. Prior to that change, slated for 2011, the FIA will introduce an energy storage regulation. “We probably would introduce a storage device that we would provide to the teams as a module,” says Wright, “and leave it to them to devise the electrical system for it.”
The FIA’s interest also extends well beyond engines and costs. After the death of former World Champion Ayrton Senna in the 1994 San Marion Grand Prix, safety improvements took center stage. Barrier crashes–starting at 40 m/sec. though increased recently–were introduced, as were a number of safety features validated through this testing. “From data, statistics, and experiments,” says Wright, “we know that if a car is protective in the test, the driver is protected in reality. The relevance to road cars is the understanding of injury mechanisms, which is becoming a very big part of the research we are doing.” Out of this work–at the track and in the lab–come more complete mathematical models of the human body and its crash response that are being shared with researchers around the world. Racing, it seems, really can improve the breed.
Dr. Diesel Would Be Proud
Audi hopes its V12 TDI race engine will advance the state of the art for production engines, and continue the company’s domination of endurance racing.
A bar in Ingolstadt, Germany, is not where you would expect the future of sports prototype racing to change, but it is where Dr. Ulrich Baretsky, head of Engine Technology at Audi Sport, sat down one night in January 2003 with a representative of the ACO (Automobile Club de l’Ouest, the sanctioning body for the Le Mans 24 Hours) to discuss endurance racing’s future. “During this conversation, we realized that 50% of the cars on the market in Europe were diesels. So why not race a diesel engine?” recalls Baretsky. The one problem was that Baretsky and his team were satisfied with the direct-injection gasoline race engine in the Audi R8, and they really didn’t want to change. That’s when–like the apostle Paul in the New Testament, as he puts it–lightning struck. “Why not do it?” he asked.
After VW Group chairman Ferdinand Piech gave his blessings at Le Mans in 2004, the first diesel race engine was running on the dyno in early May 2005. “One of our targets was to make an engine that would give diesel technology a real push.” The aluminum-silicon alloy used in Audi’s production gasoline engines (its production diesels use vermicular cast iron) is used in the block and heads of the 90? V12 TDI. Baretsky won’t divulge any secrets about the motor, except to say there are some “clever solutions found in Audi engines many years ago,” and that this technology could be applied to road engines in the future. Though relatively compact for a 5.5-liter V12, the block is heavily cross-braced, and engine masses are concentrated down low. This gives a greater area through which the diesel’s high combustion forces can be dissipated. The twin-turbo engine runs an absolute boost pressure of 2.94 bar.
“Compared to other diesels,” he says, “the V12 is light–very light–and I am sure this weight will fall as we go forward.” How light is light? Again, Baretsky is coy, but he does admit that the weight per cylinder is the same as the 3.6-liter FSI V8 of the Audi R8 that preceded it. What is lighter, however, is the five-speed X-Trac gearbox. Though the massive 1,100 Nm (approximately 810 lb-ft) of torque produced by the 650-hp V12 lets the team stretch out the gear ratios somewhat, the bigger gears and shafts necessary to handle this torque would suggest the gearbox weight should be similar to the R8’s six-speed transmission, not less.
Despite early rumors that the R10’s engine would spin to a heady–for a diesel–8,000 rpm, Baretsky insists the engine’s power band lies between 3,000 and 5,000 rpm, and the rev limit is not much beyond this. The Bosch-supplied common-rail injector system looks outwardly similar to a production motor’s, but runs to much higher pressures. “Our production car target over the next three years is to raise injector pressures to 2,000 bar,” says Baretsky, “but we are already there with the V12.” This suggests that Audi and Bosch are planning to fit hydraulically assisted injectors in place of the piezo units used today as the project develops.
Particulate traps are fitted aft in the chassis at the end of the exhaust pipes. This is not the ideal location for weight distribution, especially in terms of the chassis’ polar moment of inertia. Says Baretsky: “We’d be happier to have them closer to the engine, but this would have put them in the middle of the rear axle.” Again, the composition of the filters is secret, though he did admit the design is a new technology from Dow that is lighter than a typical particulate filter used today.
The engine control unit (ECU) is not a repurposed production unit, but one with software specifically written for this application. “There are 12,000 to 14,000 different labels you can address in a road car ECU, and functions for which we have no use,” says Baretsky. “If you took out one, it would affect all of the others. It’s better to start from scratch.” Unlike a road car ECU, the race version has a pit lane speed limiter and a start function that keeps engine rpm up when exiting the pit lane so the engine does not stall. Asked if he might at least borrow the road car’s traction control, Baretsky admits that the R10–like its R8 predecessor–does not have this function, though–since the regulations allow it–a tailor-made utility will be added to the software package. Asked how they keep the tires from wearing prematurely, especially in light of the available torque, Baretsky replies: “Good drivers!”
Another item on the jovial engineer’s to-do list is a sound system for those drivers. It’s not your typical car audio system, but a speaker system for the driver’s helmet that lets him hear the engine note as the vehicle speed rises. “Tom Kristensen [one of Audi’s lead drivers] told me they missed the information they gain from the engine noise,” says Baretsky. He estimates the R10 at full-throttle puts out about 104 dB, or about 4 dB less than the R8.
As the program moves forward, Baretsky expects it to greatly improve Audi’s diesel simulation capabilities (“Those tools came to their limits quite quickly because the boundaries we set for this project passed the normal ranges in terms of combustion pressures and things like that,” he admits.), and push the knowledge base in unknown directions. “I’m not a prophet,” he admits, “but I would dare to say the diesel world will have changed significantly–I expect a bigger push than gasoline technology has gotten over the past 60 years–in ways that benefit us all. As more competitors join us at the track, this knowledge will grow.”—CAS
The Rubber Meets The Road
Although it might seem that racing tires are in a class of their own: “It is much more difficult to design a street tire for the simple reason that the street tire has to perform under a much broader range of conditions,” says Al Speyer, executive director Motorsports, Bridgestone/Firestone North America. The underlying truth of that statement hasn’t stopped sanctioning race bodies from considering tires that can run under all but the worst weather conditions. Though it makes superficial sense, according to Pierre Dupasquier, former head of Michelin’s motorsports activities, it is quite illogical. “When it rains, a race car heads for the pits to change the tires,” he says. “It’s a luxury the road car driver does not have. You must give the racing car what it wants.”
What does a racing car want? That depends on the type of car, type of track, and the conditions under which the race is run. Take the single-seaters that run in the Indy Racing League (IRL) and Champ Car World Series. They race on street circuits, permanent road courses, short ovals, and superspeedways. “A street course has an average speed of about 100 mph, and uses our softest compound and construction,” says Speyer. It is so soft, he claims, hot tires peel the paint stripes off the road. On a permanent road course, average speed rises to 140 mph, and jump again to more than 180 mph on short ovals. “Those tires have progressively harder sidewalls and compounds to resist the heat build-up.” For superspeedway work, says Speyer, “Sustained speeds are over 220 mph, and the compounds are the stiffest and hardest we make.”
No real surprises there, except that a typical race tire has a tread face as thick as two credit cards, and requires unique processing techniques. “Racing tires have very wide, thin components,” says Speyer. “It’s a bit like trying to process a sheet of wax paper through the factory.” The techniques developed for racing tires–when applied to sturdier materials–result in less distortion, and higher quality and consistency. Technologies like long-link carbon and smoother bead design have made the move from racing to road, with the former giving greater heat resistance, longer tire life, and retaining wet weather traction as the tire wears. The latter, a seamless rounded bead, reduces vibration.
What doesn’t make the transfer–at least not in the same form–is the simulation technology used to create a new race tire. Dupasquier describes it this way: “We rely on sophisticated computer programs that allow us to look at the track right down to the granular level–to the shape of the pebbles that make up the surface. We measure the granularity, determine the abrasiveness, and look at how the corners flow together to determine the forces on the tires. This information is compared to our database of tracks, and we pull representative information in order to determine what will be needed.” Speyer describes a similar process, but adds that–since racing is a travel-intensive pursuit–“it is populated by younger engineers who move back to the passenger vehicle side of the business as their career and family needs change.” It is here–as well as through the regular meetings and design reviews–that information exchange takes place. Its value, says Dupasquier, “is that it changes the way you look at a problem, how you approach it, and what you do.”—CAS