Chrysler Corporation conducted some of the earliest aero testing in the Truck Series when they constructed this scale model of Rich Bickle’s No. 43 Petty Motorsports Dodge in 1996. Here, two Dodge engineers pose with the model giving us a perspective as to the size of the model truck. (Close Finishes Archive)

Anyone who has ever stuck their arm out the window while driving down the highway has a basic understanding of wind resistance.

Using that knowledge, consider the challenge of NASCAR Craftsman Truck Series teams as they prepare for this year’s Daytona 250 at Daytona International Speedway. Unlike the small amount of air your arm displaces at 65 miles per hour, teams are trying to counteract the effects of a 3400-pound vehicle hurtling down the Daytona Superstretch at nearly 200 miles per hour.

In short, truck body aerodynamics, or aero for short, are the critical to being at the front of the pack when the checkered flag falls on this year’s race Friday, February 18.

“Aero isn’t but a four-letter word, but it’s one of the biggest words in racing,” said Rick Crawford, winner of the 2003 Daytona 250. “It’s really become important, especially in the last six years or so. The equipment you can buy, the caliber of teams is so close, and NASCAR is keeping the rules tight to keep everyone together. That makes aero a big player.”

After several manufacturer’s tests over the past two months at Talladega (AL) Superspeedway, teams got their first chance to see the fruits of their labors when the Truck Series invaded Daytona for their scheduled NASCAR test over the weekend.

The Chevy, Ford, Dodge and Toyota contingents all got passing grades as each brand placed at least one truck in the Top-5 on the final speed charts. With that kind of competitive balance, this year’s Daytona Truck Series event is shaping up as another classic.

Pushing the nose of a 3400-pound Truck Series racer through the wind at nearly 200 miles per hour can create significant wind resistance. That’s why teams take considerable time and effort sculpting the front bumper and wheels wells to provide the best aerodynamic combination of drag and downforce. (Close Finishes Photo)

Aero testing, while relatively new to the NASCAR Craftsman Truck Series, has been around a long time. Chrysler Corporation was one of the first to enter the aero realm building a scale model of the 1969 Dodge Charger and putting it in a miniature wind tunnel at Wichita University. The result was the famed bullet-nosed, high-winged Dodge Charger Daytona.

In 1996, Chrysler used the same model building technique to test the aerodynamics of Rich Bickle’s No. 43 Petty Motorsports Dodge NCTS entry. While the technology and the process were dated, the tests proved beneficial. They also marked some of the first aero testing in the Truck Series.

According to Crawford, they probably didn’t have much to work with.

“The trucks we had back then had the aerodynamics of a brick,” he stated. “About the only thing we could do to counter that was to build horsepower under the hood and work on the chassis. We really started doing aero testing when the series took on bigger racetracks like California in 1997. We were always conscious of aero, even when we only raced on the short tracks. You wouldn’t think that’s a big deal on the short tracks, but you can help yourself with aero adjustments to the body even at a place like Martinsville. It’s what we used to call massaging the body. When we started competing on speedways above a mile in length, we really started to look to improve the drag numbers on the body and downforce for handling.”

While both the teams and the manufacturer’s took more interest in the aerodynamics of a NASCAR Craftsman Truck Series racer in the late 1990s, the testing employed few of the modern technological advancement used in aero testing today.

“Initially, we did all the testing ourselves and we did it without all the data acquisition stuff we have today,” said Crawford. “We still did it the right way. We’d go to Talladega and not touch a thing on the engine or the chassis. We’d only work on the body and the guys would watch the stopwatch. As far as I’m concerned, that’s still the best dyno in the world – the stopwatch and the racetrack. Davey Allison told me that a long time ago and that still holds true today.”

One of the most critical areas of any aerodynamic package is how the air flows over the roofline. With a 59-inch roof height, a NASCAR Craftsman Truck Series entry is nine inches higher than a Cup car making how the air flows around the A-Post (shown here) even more important in reducing the vehicle’s drag numbers.  (Close Finishes Photo)

The seat of the pants aero testing approach changed in 2000 when the Truck Series made its first trip to Daytona for the inaugural Daytona 250. According to Crawford, it was a wild west shootout compared to the locked down, regulated program that teams will experience when they go through the tech line at this year’s event.

“The rulebook was a little loose back then,” said Crawford, who started 14th but finished 34th after crashing out of the first Daytona NCTS race. “There were people who were touching their fenders on the wall during their qualifying runs to move them around and make their trucks faster. There were a bunch of other things that people were doing with their aero packages that were outside the rules. There weren’t rules made for those kinds of things back then.”

Truck Series officials quickly lassoed the aerodynamic rules package, thanks in large part to more precise testing. With the manufacturer’s contributing wind tunnel time and teams investing in sophisticated data acquisition equipment programs, NASCAR had a wealth of knowledge at their fingertips. The result was a more restricted and fairer aero rules package.

“Now there’s 18-20 templates they use to make sure these trucks are legal,” said Crawford. “I think the Fords, Chevys, Toyotas and Dodges are pretty aero alike. It’s still up to the crews to rub on them and get them fast.”

With NASCAR strictly controlling body shapes with multiple templates, it’s getting harder and harder for teams to “hide the spoiler” from the wind. Historically, massaging the shape of the roof B-Post (shown here) allows teams to direct more or less air to the rear of the truck. (Close Finishes Photo)

And fast they are. Dennis Setzer’s lap of 189.163 miles per hour paced the drafting test portion of this past weekend’s Daytona NCTS test. In all, 25 trucks topped the 185 miles per hour mark during the two-day practice. What once was a brick is now a bullet and according to Crawford, those speeds are a result of cooperation between the teams, both on and off the track.

“When we go to a racetrack like Talladega to test for Daytona, we go as a Ford group,” said Crawford. “We share information now, unlike the past where each team operated independently. Now, Ford Motor Company is involved and we’re trying to work together and make the best package. That’s also a benefit to Ford, which takes that information and tries to build the best trucks they can for the highway. They were the 2004 Truck of the Year and they want to keep it that way.”

So, just what are the teams looking for when they hit the Talladega and Daytona highbanks?

“Along with aero, balance is another big word in racing today,” Crawford stated. “Aero can hurt you if the balance isn’t right. Aero can add or detract to the balance of the truck. It’s a total package and it has to be right if you are going to go fast.

“For the superspeedways like Daytona, you’re still looking for a small amount of downforce,” Crawford continued. “Daytona is still a handling track. It’s a little rougher and you need more handling there than you would at a place like Talladega. It’s definitely not the same animal. You’re trying to get the front of the truck through the air and you’re trying to hide the spoiler a little bit with the cab. As long as you can keep the drag numbers down, get the downforce numbers up and give the driver the kind of balance where he can drive it, you’ll have a good aero package.”

Crawford and his No. 14 Circle Bar Racing Ford team hit the perfect combination of aero and balance in 2003 winning the Daytona 250. According to Crawford, a 25-year racing veteran who will make his 200th-consecutive NCTS start in the second race of the 2005 season at California, there’s nothing like pulling into Victory Lane at Daytona.

“Winning at Daytona was the utmost dream of driver from Mobile, AL,” Crawford stated. “All you have to say is Daytona, The World Center of Speed and think about making that quick little left going down pit road into Victory Lane. If Rick Crawford’s racing career ended today, he would be a success just because he got to do that. Just because of that. I can feel that inside.”