Michael Andretti Wins Title : Auto racing: He wins race and Indy car championship after Rahal drops out because of overheated engine.

Fans may never know if Michael Andretti can exercise restraint while driving his race car.

Andretti, needing only to finish sixth in Sunday’s Champion Spark Plug 300 to win his first CART/PPG Cup Indy car championship, took the lead at the start, and after his only championship challenger dropped out early, he went on to his eighth victory of the 1991 season.

Andretti, who turned 29 two weeks ago, had said that he would change his aggressive driving tactics in this race to ensure himself the championship that his father, Mario, had won four times.

But when Bobby Rahal pitted because of an overheated engine on Lap 25 of the 84-lap race around Laguna Seca’s 11-turn, 2.2-mile course, it clinched the title and its $500,000 bonus for Mario Andretti’s oldest son.

Instead of relaxing, however, he pulled away from Al Unser Jr., the defending series champion, teammates Rick Mears and Emerson Fittipaldi and Mario Andretti. No one else was seriously in the race.

“The car wanted to win, so I just let it go,” Andretti said as his father beamed at his side on the podium after the race. The elder Andretti finished third.

“I can’t think of a better payoff for the sacrifices the family has made,” Mario Andretti said. “This is what you strive for. I say, ‘Thank God for auto racing.’ It’s given the boys a job, and what more can a family ask?”

It was a big ending for a big year for the Andrettis of Nazareth, Pa. Michael won $83,700 Sunday, giving him ing $1,936,234 in purse money for the year, not counting the $500,000 PPG bonus or the $275,000 he won Saturday in the Marlboro Challenge.

The two victories, plus the season bonus, gave him $858,700 for the three-day Toyota Monterey Grand Prix weekend. A crowd estimated at 60,000 watched the Andretti show Sunday.

For the year, Mario Andretti finished seventh and John, Michael’s cousin, eighth in points. Jeff Andretti, Michael’s younger brother, was CART rookie of the year.

“It was unbelievable, ending the year like this,” Michael Andretti said. “I couldn’t have written a script any better.”

He finished the race in 1 hour 47 minutes 42 seconds and averaged 103.604 m.p.h., slower than expected because the sunny weather caused the track to become slippery.

His margin of victory was 9.2 seconds over Unser. Fittipaldi finished fourth and Mears fifth.

Andretti raced Mears to the first turn at the start. Andretti had a wheel in front when he moved over and cut off Mears, allowing Fittipaldi to move into second place. Rahal, the only driver Andretti was seriously concerned with, was content to take fourth place.

“My plan was to get the jump at the start, if I could, because once you get the lead here you have clear sailing,” Andretti said. “This is a difficult track to pass on and if you’re in front, you can dictate the pace and not take as much out of your car.”

With all eyes on the match between Andretti and Rahal, Mario Andretti made the task easier for his son when he passed Rahal on the second lap. It became a moot point 22 laps later, when Rahal dropped out.

“When Carl (Haas) told me that Bobby was out, my first thought was, ‘Let’s win this race,’ ” Michael Andretti said. “I decided to try and put some distance between my car and Al, so I’d have a cushion if I got caught in traffic somewhere.”

It was the fourth time this season that Andretti has won from the pole. The victory was a CART record eighth for a season and the 22nd of his career.

The Indy car season record for victories is 10 in 13 races by A. J. Foyt in 1964 and 10 in 18 by Al Unser Sr. in 1970, when races were sanctioned by the U.S. Auto Club.

Said Rahal, who led most of the season before Andretti caught him three races ago:

“Michael certainly earned his championship. We gave it our best shot, but the car got really hot early on, and then the oil pressure light came on and I had to bring it in.”

It has been 10 years since Andretti launched his racing career in a Formula Ford in the Sports Car Club of America’s Northeast region.

“If you’d have asked me then if I ever envisioned sitting here (as national champion), I wouldn’t have known what you were talking about,” he said. “All I was worried about was what I was doing at that time.”