Car Buffs Tune In for Tuneups

--When their do-it-yourself car-repair shop was a bust, the Magliozzi brothers started a radio talk show that is loved even by people who own nothing faster than a bicycle. Tom and Ray Magliozzi seem to know nearly every aberration in every make and model of car that ever rolled down an assembly line. And that seems to have made “Car Talk,” with about 11,500 listeners, one of the most popular shows on the National Public Radio affiliate WBUR-FM in Boston. The secret may be in the brothers’ skills at improvisation: What they don’t know, they hedge. Ray recently consoled one caller about troubles with the carburetor on his imported car: “Nobody understands the carburetor. Only four guys in Japan understand it and we won’t give them visas.” Another caller, who complained about noise in her engine, was told to turn her car radio up. Tom, 49, teaches at the Boston University School of Management and was a marketing executive until the Magliozzis opened the Good News Garage in 1973. Ray, 37, a former VISTA volunteer, still runs the business, which started as a self-help shop where car owners could rent tools to fix their automobiles and eventually became a full-service shop.

--A 240-pound producer of TV commercials chomped his way through 15 1/2 hot dogs in 10 minutes to win the 70th annual hot dog-eating contest at Nathan’s Famous at Coney Island. Mark Heller, 27, of Manhattan, tried but failed to beat the world’s record of 17 dogs consumed in 1978 by Walter Paul of Coney Island. “I feel great--at least my wife doesn’t have to cook tonight,” Heller said. In beating 23 other contestants, Heller won a plaque and a year’s supply of hot dogs. He said he decided to join the contest two years ago after a woman from West Germany won. “I said, ‘If a West German who has never eaten a hot dog in her life can win it, so can I.’ ”

--First Lady Nancy Reagan received an unexpected birthday gift--a custom-made saddle. The Reagans normally forgo gift-giving at birthdays and anniversaries. But President Reagan told his wife at a quiet dinner at the White House for her 65th birthday that the saddle would be waiting for her at their ranch near Santa Barbara, Calif., when they arrive for their customary three-week vacation in mid-August, said Elaine Crispen, Mrs. Reagan’s press secretary.

--Henry Weston, a Briton who lost almost everything he owned when his car was broken into last month in New York, completed a two-year around-the-world marathon run to raise money for the World Wildlife Fund. Weston, 24, handed a check for $1,663 to a representative of the environmental group when he finished his marathon at London’s Tower Bridge.