How NASCAR's Car of Tomorrow Works

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It has been decades since NASCAR's racers were just performance-modified versions of the cars you could purchase from the stock found at your local dealer showroom (hence the term stock car). These days, a NASCAR race car consists of a steel tube frame covered in a thin, sheet-metal body and powered by an old-school, big-displacement V-8 engine.

The racing teams build the cars based on the specifications and guidelines set by NASCAR. While the cars bear names like Impala and Fusion when they represent manufacturers like Chevrolet and Ford, the truth is, they're a world away from being anything like the car you can buy from the factory. Even the headlights are merely decorative decals.

The new cars have to weigh a minimum of 3,400 pounds (1,542 kilograms), with at least 1,625 pounds (737 kilograms) of that weight on the right side of the car. Remember, that's the side that takes most of the punishment if it goes into a wall.

Development of the Car of Tomorrow took about five years. In that time, it went through a battery of tests including wind tunnels, computer simulations and of course, on-track testing.

The Car of Tomorrow first competed at the Bristol Motor Speedway in March of 2007 and was used in 16 races that season before running every race in the 2008 season. Originally, the Car of Tomorrow wasn't scheduled to be used full time until the 2009 racing season; however, it was put into full-time use a year early [source: NBC Sports].

Just like developing a street car, there's a lot of trial and error involved in developing a race car. For instance, on the new car, foam that was designed to absorb energy during a side-impact actually melted (as a result of a nearby section of tailpipe) and spewed smoke during a race at Martinsville in 2007. Following the race, NASCAR ordered that less foam and a revised version of the heat shield be installed to protect the driver [source: Bernstein].

The Car of Tomorrow looks quite a bit different from the previous competitors in the series. In the next section, we'll find out why.

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When the Car of Tomorrow was unveiled in 2007, astute racing fans knew right away something was different. The cars were noticeably bigger, sported large spoilers on their trunk, and all of them -- regardless of whether they were Dodges, Fords, Chevrolets or Toyotas -- looked eerily similar.

The new car is several inches wider and longer than the previous NASCAR race cars which were originally introduced way back in 1981. It is also boxier, less aerodynamic and slower.

Wait a second -- a race car that's actually slower and not as aerodynamic as its predecessor? Doesn't that seem like the opposite of what engineers typically want to do? Not necessarily. In this case, NASCAR officials wanted a car that is not only safer, but also easier to control.

One of the ways they did that was to add a splitter to the lower edge of the front fascia. A splitter is a horizontal panel that extends outward from the bottom of the nose of the car to provide extra downforce. A boxier body also reduces smooth airflow over the surface. The result is a NASCAR racer that is slightly slower and a bit more controllable for the driver. They now average around 180 to 190 mph (290 to 306 kilometers per hour) on the track, while the previous design was capable of well over 200 mph (322 kilometers per hour).

But one advantage to a boxier car means there is more of an emphasis on drafting -- a classic NASCAR maneuver where a driver follows another car closely while it displaces the air in front of both vehicles. At just the right moment, the trailing car can take full advantage of this reduced wind resistance and slingshot forward to pass the lead car -- sometimes for a race victory. The less aerodynamic shape of the Car of Tomorrow makes a driver's drafting skills all the more important.

Up next, we'll look at how the Car of Tomorrow is leveling the playing field for all teams competing in the NASCAR series -- regardless of whether they're sporting Toyota or Dodge decals.

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With the inception of the Car of Tomorrow, the cars used by each of the different teams are much more standardized across the board, making NASCAR more like spec racing than ever before. Spec racing is a form of competition where drivers compete in nearly identical vehicles. When every car on the track is prepared in the same way, the race becomes more about driver skill than engineering and who has the most money to build the best race car.

The Car of Tomorrow can also be seen as a cost-saving measure for the competing teams. In previous years, NASCAR teams had to build several different cars for the various tracks on the NASCAR circuit. They built different cars for short tracks, road courses and super-speedways. The Car of Tomorrow uses the same frame, roll cage and body for all different types of race tracks. Of course, most teams do have more than one car; mainly because there's always a chance that the driver may destroy one during practice or qualifying.

But critics argue that building the new car was a multimillion-dollar investment for racing teams -- as they had to discard all of their old cars in favor of the new design -- and they won't actually benefit from the reduction in costs for years to come.

At the same time, many fans contend that making the cars more or less the same takes away from NASCAR's "run what you brung" days where a variety of vehicles raced against each other. Many fans have said that they don't want to see a spec racing series, but instead want a race where there's a reason a Dodge can beat a Ford, or vice versa.

In the next section, we'll examine the primary reason the Car of Tomorrow was developed by NASCAR: safety.

The goal of NASCAR's engineers was to build a car that could stand up to more punishment on the track than ever before, hopefully saving some lives in the process. In April of 2008, driver Michael McDowell walked away from a twisted, flaming wreck when his Toyota Camry hit the wall at 180 mph (290 kilometers per hour) and then proceeded to flip several times. Announcers at the Texas Motor Speedway on that day made mention of the improved safety features of the new cars.

The Car of Tomorrow is designed to leave more space around the driver. The cockpit is 2 inches (5.1 centimeters) taller and 4 inches (10.2 centimeters) wider, and the driver sits more towards the center of the car in order to increase the car's crumple zone. These crumple zones are designed to absorb the kinetic energy of an impact and, as the name implies, crumple during a collision. The main idea is to divert the energy of the impact away from the driver by allowing the structure of the vehicle to absorb most of the force.

The windows are bigger, too; a feature designed to allow the driver to escape from the car more quickly. In addition, the doors are filled with several inches of thick foam to help absorb impacts. The driver's-side door has steel-plated bars for the same purpose. Another engineering advancement within NASCAR's Car of Tomorrow: a more rigid driver's seat. The purpose is to better support the drivers when they experience high G-forces [source: Murray].

The fuel cell, where the high-octane racing gasoline is stored, is now smaller. It holds about 17.5 gallons (66 liters) of fuel, down from 22 gallons (83 liters) in the previous car design [source: FOX Sports]. The cell itself sports thicker walls, too. Less fuel and a thicker tank means a reduced chance of a fuel leak and possibly a big fire.

Have all of these added safety features actually worked? Has the new car proven itself on the track? Well, since the car was introduced in 2007, it still may be a little too early to tell. To date, the last person to die in a NASCAR race was Dale Earnhardt Sr. Perhaps the Car of Tomorrow can keep it that way.

By now you understand that NASCAR's Car of Tomorrow is different. But how do the fans like it? And why has Dale Earnhardt Jr. been so critical of it in the media? We'll find out why in the next section.

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Despite being a big leap forward in driver safety, the Car of Tomorrow has been a hard sell to NASCAR's diehard fan base.

NASCAR fans have expressed their displeasure of the Car of Tomorrow on many levels. Many don't like the increased size of the car, the way it looks, the boxier shape, the reduced on-track speeds and the way the various competing manufacturers now run nearly identical machines. But the fans aren't the only ones complaining.

Drivers have criticized the car's handling. Many have complained that they have to re-learn their driving strategies at the same tracks they've always raced on. Many drivers say the car doesn't turn nearly as well as the old one, and that aero push -- an effect of airflow (or rather, lack of downforce in a draft situation) that seemingly pushes a trailing car towards the wall in turns -- is much worse than before, while the new car was supposed to solve that problem.

Dale Earnhardt, Jr., whose father's death in 2001 spurred development of the car, has been openly critical of it. "I think ... the car isn't a finished product," Earnhardt said in October of 2008. "Whenever they decide to move forward and evolve and let that car change and become a better race car, we will be ready to do that. But until then, we really don't have a choice in the matter" [source: NBC Sports].

Those who support the car say it has placed greater emphasis back on driver skill. Others say that protecting drivers' lives should be placed above an exciting race, and that a safer car is better for everyone involved in the sport. At the same time, Earnhardt and several other drivers conceded that the car is being improved gradually with each passing year. Plus, NASCAR has no plans of getting rid of it. It appears that the Car of Tomorrow is slated to be the Car of Today for a long time.

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