INDIANAPOLIS (AP) — IndyCar CEO Randy Bernard is an optimist when it comes to putting 33 cars in this year’s Indianapolis 500.

A.J. Foyt is a believer, too.

The trick, of course, will be making it happen. On Sunday, Bernard offered to help find sponsors, engines and any other assistance to assure the traditional starting field is full for the May 27 race.

“We haven’t had a race since 1947 that didn’t have that many cars (33) and we have to do everything we can to make sure we get 33,” Bernard told The Associated Press.

Of course it wouldn’t look good to break with tradition now, a season in which IndyCar officials have put a brand new car on the track and brought back turbocharged engines.

But it’s not the first time this debate has been waged around the historic 2.5-mile Brickyard oval. There were similar questions in 2003, the last time the series changed cars, and it was a consistent question in the early days of the IndyCar-CART split back in the 1990s.

“Have you ever seen, in your life, the Indianapolis 500 start 31 cars and not 33?” Foyt said. “What makes you think that’s going to happen now? I’m quite sure the field will be full.”

The difference this time is that there’s a smaller margin of error.

With only 33 car-driver combinations and the Chevrolets and Honda engines almost all divvied up, filling spots with new cars will be a challenge.

Spare parts are hard to come by, too.

The key to making everything work could be Dragon Racing.

Through two days of rookie orientation and the first two days of full practice, neither of the two cars owned by Jay Penske has logged a lap. The team had used the struggling Lotus engines through the first four races this season. Now Penske has filed a $4.6 million lawsuit against Lotus, claiming the company had damaged Dragon’s reputation by spreading “especially outrageous” falsehoods, failing to deliver two chassis and hurting its ability to be competitive.

Penske has spent most of this week working on a resolution so his drivers, France’s Sebastien Bourdais and English rookie Katherine Legge, can start practicing.

Series officials met with Penske after the league adopted a new rule requiring IndyCar’s permission to change engines. The pending suit may also force Penske to get either a court injunction or a release from Lotus to make a change.

The league’s vice president of technology, Will Phillips, said discussions are continuing.

“We’ll do what we can to help because we want them to be here,” Phillips said. “We want to make sure we follow through on the tradition and fill the field and to do that we have to work with all three (engine) manufacturers.”

On Sunday, Dragon crew members at least were moving tires into a garage that had been empty the previous three days.

Until something is worked out, though, drivers can’t do much.

“We’re trying to focus on the things we can control, so that when we get engines, when we get on the track, we’re ready to go,” Legge said Saturday. “We know it’s in everybody’s best interests to get on the track as soon as possible.”

Many in Gasoline Alley believe Penske’s better-known father, Roger, will somehow come up with two Chevrolet engines for his son. Ed Carpenter’s backup car is one possibility, but that is the 15th and final Chevy engine the company has committed to for May. Carpenter could hire a driver or make the car available to another team, some of which have already expressed in purchasing the car.

Chevy spokeswoman Judy Kouba Dominick was not sure if the company would make any additional engines available before qualifications begin next weekend.

Dragon Racing’s uncertain status isn’t the only potential obstacle at Indy.

Former Formula One driver Jean Alesi had the slowest car Saturday and it wasn’t much better Sunday, when he was second slowest. He still hasn’t topped 209 mph and must run sustained laps of 210 mph or better just to pass his rookie test. Alesi’s best speed Saturday was 205.265. Only Simona de Silvestro was slower, at 202.179. Both are using Lotus engines.

The gap was huge, too.

Six drivers topped the 220 mark, led by Colombia’s Sebastian Saavedra at 221.526. American rookies Bryan Clauson and Josef Newgarden were next, at 221.173 and 221.158, with two-time IndyCar champ and 2008 Indy winner Scott Dixon fourth at 220.829.

Late-week crashes could also pose a problem with Brazil’s Ana Beatriz, Clauson and Saavedra not listing any backup cars on the entry list.

Does it really matter if the race starts with less than a full field?

“Not to me it doesn’t,” Team Penske’s Ryan Briscoe said. “But if you have a bad week, that takes the stress off Bump Day. I think everybody wants a good Bump Day, and I think you’d always love to see 33 cars.”

Others are more sentimental.

“I love the tradition of Indianapolis and I’m disappointed we don’t have more cars here though I know there are a lot of extenuating circumstances,” said Mike Hull, managing director for Target Chip Ganassi Racing. “The fact that we’re even discussing this is disappointing to me.”

Since the first Indy race in 1911, 21 of the 95 races have started with something other than 33 cars.

Fourteen times, the number topped 33, including 35 in 1979 and 1997. Only seven times has the race started with fewer than 33 cars, the last being 1947 when team owners and drivers were involved in a contract dispute with the speedway and slow speeds in their post-war equipment produced only 30 starters.

While the number is based on a formula originally devised by the race’s first sanctioning body, the Contest Board of the American Automobile Association, to provide a safe distance between the cars, the No. 33 has become an essential part of Indy lore.