The races may be about competition and entertainment, but the business of NASCAR is business.

For the car manufacturers who participate in Sprint Cup — Ford and Chevrolet, Dodge and Toyota — the essential point is using the visibility of racing to help sell street cars in showrooms.

The famous phrase "Win on Sunday, sell on Monday" gained traction for a reason.

Yet in recent years, the fear among NASCAR constituencies is that some of the brand identity that moved race fans to buy the same model car that their favorite driver wheels has been lost.

"I think the manufacturers and NASCAR absolutely need to do something," says Mel Poole, a Charlotte, N.C.-based sports marketing guru. "The sport has been losing steam in terms of ticket sales, TV (ratings) and sponsorship dollars."

Starting in 2013, NASCAR and its car manufacturers are going to try to put a bit of the "stock" back into stock-car racing. The plan is for the Sprint Cup cars driven by Dale Earnhardt Jr., Kyle Busch and friends to again resemble — externally — the street-car models upon which they are based.

When the Sprint Cup Series returns to Kentucky Speedway on Saturday night with the second Quaker State 400, it will be the last time that the current edition of race cars — the large, boxy design known as the Car of Tomorrow — will run in Sparta.

"We were concerned about our product relevance," says Robin Pemberton, NASCAR vice president of competition and racing development. "We had a lot of conversations with the representatives of the (car) manufacturers. They were ready (for a change) and we were ready."

Already, Ford has unveiled its new 2013 Fusion race car, which looks sportier than its current Sprint Cup entry. Toyota has publicly shown its 2013 race Camry, which is designed to look much closer to the Camrys that roll off the assembly line in Georgetown.

"I feel like we've been able to get the 2013 Cup race car pretty doggone close (in appearance) to the Camry that Toyota sells in showrooms," says Les Unger, Toyota national motorsports manager.

(General Motors has announced it will be running the Chevrolet SS next year in NASCAR but has not yet unveiled the new race car to the public. Dodge has presented a new 2013 Charger, but with the impending move of Penske Racing to Ford for next season, does not presently have a team signed to run Dodges in Sprint Cup next year).

In simple terms, NASCAR has relaxed its rules on how Sprint Cup cars have to look above the doors, hood and trunk lid. That has given the manufacturers a chance to return some personality to their race cars.

"Every piece of sheet metal on our (new) car is different," says Pat DiMarco, Ford Racing operations manager.

The goal is for NASCAR fans in 2013 to be able to differentiate with the naked eye a Ford Fusion from a Toyota Camry from a Chevrolet SS (and from a Dodge Charger, if there are any) on the racetrack.

For the manufacturers, designing the new race cars has been a chance to integrate their racing operations into their larger companies.

Ford's DiMarco says the 2013 racing Fusion worked its way through the same design process that the company's street models go through right up to a review by Ford President and CEO Alan Mulally. Toyota gave its U.S. design facility the job of making its new race car look as close as possible to the street Camry, Unger said.

What isn't changing in any major way is what is beneath the sheet metal of the 2013 Cup cars. "Underneath the skin, these remain specialized race cars," Unger said.

Even with the changes, one thing NASCAR is insistent on "is that the new cars be as safe as what we've been running with the Car of Tomorrow," says Pemberton.

What should be fascinating going forward is whether the manufacturers can all race visibly different car bodies yet none gain an aerodynamic advantage (or conversely suffer an aero disadvantage) that impacts competitive balance on the track.

"It's a challenge, and it's going to be a challenge," says Pemberton. "There is a lot of sophisticated wind tunnel testing available now and we're putting (the new car designs) through those tests. We think we can preserve the balance of competition we have now, but that's something we have to continue to watch."

The overall goal behind the switch to race cars that more resemble street cars in Sprint Cup is to make fans more apt to buy.

Poole, whose firm SponsorLogic helps in the development of financial sponsorships, says rolling out the new cars is only a first step and will not by itself be enough.

"I don't think it will matter unless the manufacturers really get behind these cars with big promotional campaigns that make sure the customers know there are new cars that look like what is available in the showrooms," he says. "Then the manufacturers need to have street cars in the showroom that is a hot rod that people want to buy when they show up. Just having these new cars to race is only a first step."

There's obviously much at stake. Ford's research shows that 38 percent of new car "intenders" are motorsports fans, says Tim Duerr, Ford Racing marketing manager. Of that 38 percent, 78 percent are NASCAR fans.

Of race cars again resembling street cars, "I predict it is gonna be huge," Duerr said. "I think fans are really going to relate to cars that look like what they can drive. I really believe in time you'll see a boost in sales."

That, ultimately, is what this is all about.

Mark Story: (859) 231-3230. Email: mstory@herald-leader.com. Twitter: @markcstory. Blog: markstory.bloginky.com