Stock car racing, NASCAR-style, is more like NFL football than it is open-wheel racing. Fenders mean there’s a little bit of “wiggle” room when you’re three-wide and faster than the other two, and the chrome horn is not a trophy, but an attitude.
At Daytona, however, it’s a little different. NASCAR teams are dialing up the engineering in an effort to make their “stock” cars lighter, more slippery and, at the end of the day, faster than anyone else’s. That’s because restrictor plates are in use, and that robs horsepower and speed.
Where to start?
How about the body? The bodies on the Chevys, Dodges, Fords and Toyotas used in NASCAR competition are all pretty standard, but as is often said, the devil is in the details. NASCAR allows a certain amount of arranging when the body is hung on the chassis, but not enough to make a huge difference.
The devil-detail connection happens when you start to add color to the primer.
Whether it’s a wrapped car—full-body decals—or a painted one, the idea is to make it slice through the air. There are many ways to do that, starting with the finish.
Depending on which team is doing the prep, the processes are specific. Some teams paint the car one color, add the decals and put on a clear-coat finish to get the edges of the decals out of the air.
You might think that is wretched excess, but it isn’t. Studies have been done on this very thing, in the wind tunnel, and you’re talking fractions of grams of drag. The teams will take as much drag out of the equation as possible, and some even hand-paint the decals onto the car to get it done.
Another way to do that is, after the decals are applied and the clear-coat sets, taking a wet sander to the finish to scrape every last blemish and bubble out of the body. Back to the wind tunnel for a final swipe with the Lionel train-smoke wand, and they’re off to Daytona.
Some teams even apply a slippery substance (Teflon®-based) to the suspension pieces and the undersides of the cars to make them go through the air a little cleaner, though not much air gets through the new nose and under the car these days.
Air won’t turn a corner, but it will follow a curve, and the smoother the curve, the faster the air flows over it. That’s downforce, not drag, and it is sought out like the map to the City of Gold.
Remember, we’re talking miniscule amounts of drag here, and teams will change normal hex bolts to smooth-topped buttons to reduce it. And that’s UNDER the car, too. While five bolts so changed might not make a difference, 45 or 50 will, and teams have the numbers to back it up.
Anything that can possibly add drag is pored over and reduced, if possible. Fender braces, body brackets, NACA-duct openings…you name it, it goes under the microscope and through the wind tunnel. Fender openings get special attention too, tucked as tight around the wheels as possible to reduce the possibility of air getting underneath and into the body work.
Inside the car, innocuous things like wiring harnesses, shifter boots and the like are optimized to be air-tight or slippery, depending on where they are. The air flow to the driver is arranged so that whatever drag it produces is minimized (NACA ducts are the funny-shaped inserts in the windows, and they blow air on the driver, the oil cooler, dry sump and transmission housings.
Even the brakes are gone over with a fine-toothed comb. At Daytona, the teams use the smallest pads and calipers they can and still stop the car on pit road, and the brake fans are located out of the slipstream as much as possible. If you’re using the brakes at Daytona, you’re either avoiding a wreck or dragging to stay in the draft and not start The Big One on your own hook.
This year, with the new pavement at Daytona, the tire temps should not be high enough to melt the bead of the tire, but you can never be sure, so bead blowers will likely still be in use, according to one Toyota crew member.
Everything that can be lightened, smoothed or otherwise polished is, all in the search for one less ounce of drag and one more ounce of downforce.