The Unsers are family, and they do things together -- whether it be hurtling around an oval track or meeting a president.

"It's your basic close-knit family," said Al Unser Jr.

Al Sr. and his brother Bobby are veterans at racing and chatting with the nation's leaders. Al has won three Indianapolis 500s and Bobby has won two. Both have met Presidents Nixon and Ford. But for Al Jr., though not a rookie in racing circles since 1983, this chief executive stuff was all new.

"It was a great honor," said Al Jr., who, with his auburn hair and freckles, doesn't look his 23 years. "I had more butterflies than I did in my first Indy 500."

The Unsers and their wives were at the White House yesterday afternoon at the suggestion of their congressman, Rep. Manuel Lujan (R.-N.M.) and the invitation of President Reagan.

Al Unser Sr. presented President Reagan with the yellow racing helmet that he used this past season in winning the CART Indy Car World Series driving championship. He won it with 151 points, only one point better than his son, who is half his age.

Al Jr. made his first Indianapolis 500 start in 1983 and gained his first Indy-car win in Portland in 1984. But in 1985, he won two races in a row: the U.S. Grand Prix at the Meadowlands and the Budweiser Cleveland Grand Prix.

Yesterday, Al Jr. discussed that Meadowlands victory with Reagan.

"When I won at the Meadowlands (June 30), the (TWA) hostages were being released," he said, "and the President came on the TV to tell American people that the hostages had been released. And I told him that when he did that, he interrupted my victory circle speech. Then I told him that only presidents can interrupt a victory circle speech."

This is the offseason for Indy car racing, but Al Sr. said there is still plenty of work to be done, testing cars and looking for ways to go faster.

The trip to Washington was just a break in the action and a chance to meet a third president.

"It's a rare treat," Al Sr. said. "This is one of the good things that comes along with racing."

Although the son is just beginning his racing career, the father is nearing the end of his. Last year he had intended to run in only three major races. But when Rick Mears was injured, the Pennzoil racing team asked Al Sr. to step in and guide its top car. The results were impressive. He won the Phoenix 150 and Domino's Pizza Triple Crown championship by finishing fourth at Indianapolis, second at Michigan and third at Pocono.

Having his son racing with him only made it better.

"After seeing what he's become," Al Sr. said, "it's a lot more fun."

And he still has plenty of confidence in his driving.

"I'm stronger and smarter," he said during a tour of the Pentagon. "Age will do that to you. I feel as confident now as I did 10 years ago."

Al Jr. said he thinks his father could last another 10 years on the circuit if he competes in only three or four races a year.

"He's only 46," said Al Jr. "He's in good shape, physically and mentally."

No matter how long Al Sr. remains a competitor, this past year will remain in the mind of his son, who, since he began racing at the age of 9, has wanted to run against his idol. "It was just great," Al Jr. said of their competition, camaraderie and success. "I couldn't have asked for another person I'd rather race against more."