Jack Elder received no "Dear Jake" letter when he quit his job as chief mechanic for Grand National star Dale Earnhardt.

Elder is quoted as saying team manager Roland Wlodyka could "foul up a five-car funeral." A lack of organization and, perhaps, Elder's pay are to blame. He got about $28,000 a year for his seven-day work weeks.

Still, Earnhardt now leads the Grand National Winston Cup standings with 2,260 points going into today's Michigan's 400. Second is Richard Petty with 2,219, with Cale Yarborough, 2,174, in third.

In winning the Texas 400, Yarborough joined Petty as the only Grand National drivers to have won more than $3 million in their careers.

There are new names among the winners at the 30-year-old Dorsey (Md.) Speedway. Two-time winners this season include Bill Hynes of Catonsville, sportsman-modified class; Tom Crummitt of Frederick, Figure Eight, and Jimmy Skinner of Glen Burnie, street stock.

The slick quarter-mile dirt track has more than 100 cars racing Saturday nights. Action now begins at 7 p.m. with the first of a dozen races.

At Old Dominion Speedway in Manassas, track publicist Skip Potter has retired from street-stock racing for a while. His sedan spun on a slick track, bounced off the safety fence and came to rest in midtrack. Since he was running in the middle of the pack, Potter and his car were tapped by some of the 26-car field as they went by. "It's sitting out back now waiting until I get time to repair it," said Potter, who was not hurt.

Janet Guthrie's car has been entered in next Sunday's True Value 500 at Pocono (Pa.) Raceway, but not Janet. She has one race to go on her contract with Texaco.

After failing to qualify for Indianapolis, Guthrie pointed out her new car had fewer than 250 test miles when it arrived at the speedway, and none with her at the wheel. "I won't be back under these circumstances," she said.

In England, South Africa's Desire Wilson is having a great season as Europe's leading woman driver. Teamed with Alain de Cardenet, she won Monza, Italy and Silverstone, England World Manufacturers Championship races. Earlier this year, she became the first woman to win a Formula One race by taking an Aurora title event in England.

National motocross champion Kent Howerton insists on one-year contracts for his services. The 25-year-old Suzuki rider says, "If I'm not good enough for another contract, I don't deserve one in the first place."

He will be in the $50,000 finals of the Supercross series Aug. 8 and 9 at Philadelphia's JFK Stadium. The series is contested over dirt courses in the nation's major enclosed and open arenas.

If you have ambitions to become a Grand Prix driver, you may be able to rent a ride in the competitive Formula Atlantic series for about $200,000 a season. But, only the "right kind" of driver gets a car, says Pierre Phillips, who rents the racers.

His kind of guy is 20 to 26, does nothing but race and is willing to invest two years in the program. Purses are about $30,000 for each of the nine title events.

Phillips puts you in a race-ready machine and handles all upkeep. The formula, also popular in Europe, allows cars with 97-cubic-inch engines putting out about 215 horsepower.

Trenton (N.J.) Speedway is facing extenction. The 1.5-mile oval that had Indianapolis-car races every year until this season is up for sale at public auction Aug. 19. The tract and surrounding fairgrounds covering 135 acres are said to be worth about $2 million.

In contrast, major improvements are being made at the Richmond Fairgrounds' half-mile oval. The infield is being lowered for better sight lines, 5,000 metal seats are going in and new toilet facilities are being installed. Promoter Paul Sawyer said racing will continue at the Fairgrounds "even if and when" his proposed superspeedway in Dinwiddie County is built.