Best drivers in the world? It's relative

CHARLOTTE, N.C. -- AJ Allmendinger is somewhere between the 15th- to 25th-best driver in NASCAR's Sprint Cup Series, and he qualified fifth for Sunday's Indianapolis 500. So put five-time Sprint Cup champion Jimmie Johnson in the same Penske Racing car and he'd probably win the pole.

He might even be a threat to win.

It seems logical, right?

It's not that simple.

As much as NASCAR likes promoting itself as having the best drivers in the world, that doesn't automatically mean they would be the best drivers in IndyCar or any other series.

It's the same for top IndyCar drivers transitioning to NASCAR. Sam Hornish Jr. won three titles in IndyCar and an Indianapolis 500, but he can't get a ride in the Cup series after losing the one he had two years ago because of a lack of performance and sponsorship.

So the debate goes on, particularly on this weekend when the motorsports spotlight shines the brightest with the Indianapolis 500, Coca-Cola 600 at Charlotte Motor Speedway and Formula One's Monaco Grand Prix all taking place on the same day.

Who are the best drivers in the world?

"You ask if NASCAR drivers are the best in the world," two-time Indianapolis 500 champion Al Unser Jr. said. "Absolutely. Driving in NASCAR they are. And the top drivers in IndyCar are the best in the world of IndyCar.

"The top drivers in the World of Outlaws are the best in those cars. I was, in the '80s and '90s, one of the best Indy car drivers in the world, and I went over to NASCAR but I was schooled."

Schooled is a bit harsh. Unser was running fifth in his only Cup start, the 1993 Daytona 500, when he was wrecked by Dale Earnhardt with about 10 laps to go. In 53 International Race of Champions events featuring the top drivers from all motorsports in identically prepared stock cars, Unser won 11 times.

If given time, he might have adjusted to a Cup car, and there's a part of him that wishes he had.

But there are no guarantees -- even for a driver as talented as Johnson -- that being great in one series will make you great in another.

"The driver, what we become is a product of what we grew up in," Johnson said as he prepared for the 600. "My off-road days, the vehicles I raced, helped lead me to NASCAR. I've never been in an open-wheel vehicle, a Formula-style vehicle. They just drive differently.

"If I just left [NASCAR] and tried next year, tested a couple times, I wouldn't be where Dinger is. He's doing an amazing job, and I would love to see him win that thing."

It's not out of the question. In many ways, a NASCAR driver competing in the Indianapolis 500 is like an IndyCar driver competing in the Daytona 500 -- particularly when it comes to qualifying, where it's basically all out for one lap.

Put a driver in top equipment, as Allmendinger is with Penske Racing at Indianapolis, and he's a threat for the pole for the same reason former IndyCar star Danica Patrick was able to win the pole for this year's Daytona 500.

That's why, in the 1960s and '70s, when NASCAR and open-wheel drivers switched back and forth regularly, Indy and Charlotte were the two races they participated in more than any other. They knew those were the easiest to transition to and possibly win, not to mention the money was there. That the two races were held on different days then helped.

Four-time Indianapolis 500 champion A.J. Foyt counted the 1972 Daytona 500 among his seven wins in NASCAR. Two of his other wins were in the July race at Daytona.

And for the record, if there's a driver you want to call the best ever in motorsports, Foyt is your guy. He actually was named one of NASCAR's 50 greatest drivers in 1998 when the sport celebrated its 50th anniversary.

Legend Mario Andretti, the only other driver who won the Indy 500 and Daytona 500, won NASCAR's premier race in 1967 and had three top-10s in the event.

Unser isn't sure even that would happen in today's world, noting NASCAR is "way more competitive nowadays" and getting a one-off deal in a top car is much tougher because of sponsor demands.

But drivers have egos like athletes in all sports, and many believe that, with the proper training and equipment, they can succeed in anything with wheels.

NASCAR Hall of Famer Bobby Allison still believes he would have won the Indy 500 were it not for mechanical issues in his two attempts. Maybe he could have. He finished sixth in the only one of the six open-wheel races in which he competed that parts didn't fail.

"Back in the early days, racers were racers, so whatever I got in, I wanted to go fast. … I wanted to win," Allison said. "If I had stayed in the Indy cars, I'm sure I could have won. And maybe if I had gotten an early win, they could have kept me there."

Racers still like to prove they can drive anything today. Kurt Busch, who will start second to pole sitter Denny Hamlin in the 600, recently jumped in an Andretti Autosport Indy car and posted a top speed of 218 mph with no prior seat time.

That was about 10 mph below Ed Carpenter's pole speed for the 500 but was impressive enough that it made Busch eligible to attempt the double if he felt physically prepared for 1,100 miles in one day.

But even Busch, a top-five driver in talent in NASCAR, is realistic enough to understand the transition between the two series would be difficult.

"There are 33 drivers who make the race at the Indy 500, and a top-tier NASCAR guy can make the show," he said. "Will a top-tier driver know how to adjust to the draft and do it successfully first time out? Probably not.

"There are a lot of things you have to study, forecast and to predict, so it's difficult to crack into anything and find success the first time out. Everyone is so specialized in every bit of their form of motorsport it makes it tough to swap over and find success right away."

There's still a perception that the top drivers in motorsports are in NASCAR. It was fueled in recent years by the defection of 2000 Indy 500 winner Juan Pablo Montoya, three-time Indy 500 winner Dario Franchitti, Hornish and Patrick to the Cup series.

Three-time Cup champion Tony Stewart has an open invitation from Roger Penske to drive in the 500.

What Allmendinger did on Pole Day opened eyes.

But perception isn't reality for the most part. Montoya was a star in every other series he participated in before coming to NASCAR, but here he has only two road course wins in 228 starts and is 22nd in points.

Franchitti made only 10 of 17 races in his brief venture into stock cars before his team was shut down for financial reasons.

A big reason Stewart has an open invitation is because he was a star in open wheel before coming to NASCAR, winning three times in 26 events and claiming the 1997 Indy Racing League title. In his two attempts at the Indianapolis 500 -- 1999 and 2001 -- after joining NASCAR, he finished ninth and sixth.

So he has the background to succeed in both.

So does Allmendinger, who had five wins in 40 Champ Car World Series races before moving to NASCAR in 2007.

"AJ is doing it this year, but he's obviously got a strong IndyCar background, so it's a bit different than if Kyle [Busch] or Jimmie [Johnson] were going to do it," said Patrick, who had a win and seven podium finishes in IndyCar before making the switch to stock cars, where she is winless.

Drivers crossing over is just cool for the fans. If you're a race fan, how cool would it be to follow Jimmie [Johnson], Kyle [Busch] or Jeff [Gordon] if they ran the Indy 500? Just putting them in a completely different element than they're used to would be incredible to watch.

-- Danica Patrick

"A guy like Jimmie would be great in the Indy 500 because he's smart and patient. But if he's doing a one-off and going up against Dario and Helio [Castroneves], both of who have been with their teams for a long time … that's a lot to go up against."

In other words, it's not all about talent.

And it's anything but easy.

Allmendinger, even with the benefit of open-wheel experience and top equipment, admits his IndyCar experience this year has been "some of the toughest racing I've had."

Part of that is because he spent so much time training for NASCAR.

"Rookie orientation was funny because, that first lap, that left foot went right to the brake pedal, and it was, 'No, no, no,'" Allmendinger said. "I tried to make my NASCAR line and about ran through the grass before I turned in, but I was very fortunate."

So it's not simple. That's one reason Speedway Motorsports Inc. chairman Bruton Smith in 2010 offered $20 million to any driver who could win the Indianapolis 500 and Coca-Cola 600 on the same day.

No driver stepped forward. They, like Smith, knew the odds of winning both were so astronomical that it wasn't worth the time or money to attempt it.

So who has the best drivers in the world? There's no way to fairly say. It's like trying to figure out whether Johnson is as good as Richard Petty or David Pearson in NASCAR. You can't compare.

But it's a fun debate, one that comes around more on this weekend than any other in motorsports. And it's sad in a way that it's become almost prohibitive in terms of time and money for drivers to do the double as they once did routinely.

"Drivers crossing over is just cool for the fans," Patrick said. "If you're a race fan, how cool would it be to follow Jimmie, Kyle or Jeff [Gordon] if they ran the Indy 500? Just putting them in a completely different element than they're used to would be incredible to watch."

It also would be an incredibly difficult feat with no guarantee for success.

"The truth of the matter is, the best drivers in the world are the top drivers in F1, NASCAR, IndyCar, dirt cars and the NHRA," Unser said. "You have to adapt to whatever you're driving, and if you're able to do that, then you're going to run at the front.

"Only then are you one of the best drivers in the world in those cars."