NASCAR makes fuel injection sound like it's some new marvel Almost all race cars have been using fuel injection for decades. Antiquated NASCAR is just now adopting it. In the following press release NASCAR is making it sound as though it's some new marvel that its fans should go gaga over. From the press we have seen one might even think they invented fuel injection, soft walls, HANS Device and every other improvement in racing. The fact is they are the last to adopt anything new.
Simply put, NASCAR's move to electronic fuel injection hasn't gotten the press it deserves. There have been more pressing concerns. The sanctioning body and Sprint Cup teams were so focused on rule changes designed to break up sustained two-car drafts during mid-January tests at Daytona International Speedway that the impending competitive debut of EFI went virtually unnoticed. Nevertheless, the introduction of EFI represents a profound change that goes far beyond bringing Cup racecars closer to models found in the showroom. Here are the basics:
* The fuel delivery system is fundamentally different. Injectors shoot fuel into each individual cylinder, as they are programmed to do by computer. Instead of a carburetor that mixes air and fuel, a throttle body provides airflow to the engine. As Sprint Cup series director John Darby put it during a meeting with reporters Monday at NASCAR's research-and-development center, "The engine architecture is the same. We're squirting it (fuel), instead of sucking it."
* There are more parts and pieces. To run the EFI system, NASCAR has contracted with McLaren to provide an electronic control unit, powered by software from Freescale. An array of sensors provides performance data to the ECU, which is mounted on the engine. With a few keystrokes on a laptop computer, engine tuners can construct an ignition timing map that will regulate fuel flow to the cylinders based on input from the sensors.
The implications for Cup racing are far-reaching. Teams can plug into the ECU post-race and use the after-the-fact telemetry to make performance decisions. Traditionally, NASCAR has taken a firm stance against real-time data acquisition, and that won't change.
But teams will be allowed to download data after practice and qualifying and make adjustments to the EFI system. What they won't be able to do, however, is read data during a race, and -- realizing that fuel mileage may determine the outcome, for example -- reset their systems to a mapping more conducive to fuel conservation.
Accordingly, plugging into the EFI system adds an additional layer to NASCAR's inspection process. Before a race, the ECUs will be "locked" to one configuration for the duration. After the event, NASCAR will inspect the top five and random cars.
In keeping with its tradition of an open garage, NASCAR will also collect data and share it among the teams. But when Roush Fenway Racing, for example, sees information from a Hendrick Motorsports ECU, it will be broad-brush data rather than examination of minutiae.
In other words, RFR won't be able to compare where Carl Edwards lifts on corner entry as opposed to Jimmie Johnson. Each team will have specific information about its own cars but much more general data about its competitors. Nevertheless, the information should prove useful, particularly, as Darby says, "to get the little guys up to speed quicker."
Before its debut at Daytona, EFI has been tested extensively. Based on those tests, and on a critical mass of issues that have surfaced in a chat room established by McLaren, there have been approximately eight software revisions since NASCAR began testing the system.
Though McLaren has a history in Formula One and other forms of racing, the company had never dealt with a NASCAR engine, which Darby characterized as "the biggest, most bad-ass thing in motorsports, other than drag racing." McLaren has never had a competition failure with one of its ECUs, but neither has the company dealt with a racing series that puts as much stress on its engines. "If it's going to fail, we're going to fail it -- I guarantee you that," Darby said.
Though there has been much discussion of fuel economy with the switch to EFI, the consensus is that savings will be negligible. Nevertheless, EFI will allow tuners to achieve a higher level of efficiency in their fuel-saving measures.
One thing won't change: the inverse relationship between fuel economy and horsepower. To save gas, you have to give up power under the hood. But EFI, particularly as teams become more familiar with its nuances, will allow the engine to be tuned to a particular competitor's driving style, thereby enhancing the performance of both man and machine.
Restrictor Plates: NASCAR will require EFI engines to use a restrictor plate at the sport’s two longest and fastest tracks: Talladega Superspeedway and Daytona International Speedway.
The plate will be placed beneath the Holley EFI throttle body and limit the amount of air made available to the engine. Unlike carbureted engines, Sunoco Green E15 will not pass through the restrictor plate openings. (NASCAR Wire Service)