The Reagan administration is stripping away auto safety regulations to help domestic automakers reduce production costs and sell more cars, says former auto safety director Joan Claybrook.

Claybrook, in a 92-page report released today, also accuses the administration of conspiring with automakers to junk her old agency, the National Highway Traffic Safety Administration.

"The Reagan administration is not deterred by law or science or history or the sanctity of life" in its alleged attempts to "compromise safety quality to compensate for Detroit's inability to sell cars," Claybrook said. Her comments are contained in a report, which she co-authored, that was published by Public Citizen, the umbrella organization for various groups founded by corporate critic Ralph Nader. laybrook, once a target of Nader's criticisms during her reign as NHTSA chief under President Carter, now presides over Public Citizen. That turnabout was cited by current NHTSA administrator Raymond Peck, who said Claybrook's report is "5 percent accurate, 100 percent predictable and 1,000 percent political."

But Claybrook's basic argument -- that the administration has deemphasized NHTSA's role in auto safety at a time when financially pressed automakers are praying for regulatory relief -- is supported by others, for quite different reasons. Since its inception in 1966, NHTSA has been a troublesome agency, complicating automotive production with costly, unnecessary, often unmarketbale safety standards, according to Rich Ceppos, associate editor of "Car & Driver" magazine.

The magazine, popular among car buffs, recently ran an article by Ceppos celebrating "the decline and fall of the safety fanatics."

"For the first time in the history of the National Highway Traffic Safety Administration, we're witnessing a widespread rollback in safety standards -- seventeen in all" since President Reagan took office, Ceppos said in the article. "Clearly, Washington is no longer convinced that we need to be saved from our automobiles. This change of heart is more than good news: it's cause for celebration."

Ceppos offered his own five-point program for road safety, part which included raising interstate speeds to 80 miles per hour, up from the current 55 mph limit, "to prove once and for all that our major highways are safe." Claybrook and her co-authors, Jacqueline Gillan and Anne Strainchamps, said the administration is bringing about that suggested change through default.

"The 55 mph speed limit is credited with saving more than 54,000 lives and 28 billion gallons of gas since it was established in 1974," the authors said. But despite "strong public support" for retaining the law, the administration "is circumventing the program" by stripping away federal funding for speed law enforcement projects and eliminating technical assistance to the program, including money for radar development.

The administration also has worked with automakers "in the secret handling of auto defect recalls and investigations, and the abandonment of information and education programs" about available auto safety technology, the authors said in their report.

The report strongly criticized the administration for ditching requirements for automatic safety mechanisms, such as air bags, in cars. And it questioned the wisdom of NHTSA's cooperation with automakers in conducting side-impact crash tests on cars. The tests ultimately are supposed to yield new federal safety standards for doors and other barriers that could protect auto passengers from lateral collisions. ichael Finkelstein, NHTSA's administrator for research and development, denied conspiring with automakers to weaken standards or to otherwise undermine his agency.

"That's silly," Finkelstein said. "The information we've developed is available to anyone who wants it. The agency isn't hiding the fact that we're talking to GM or Ford or anyone else." He said such cooperation is necessary because the agency has found that it can make good standards, but that it can't make good cars.

"The market is too volatile for the government to intelligently regulate" all matters related to auto production, Finkelstein said. But he said he agrees with Claybrook that the administration should not have rescinded the air bag requirement. "I was against doing that," he said.

Finkelstein said the changes taking place at NHTSA and other federal regulatory agencies are the products of philosophy, instead of conspiracy. "Under Claybrook, the burden of proof clearly was on the industry to show why it shouldn't be regulated. Under this administration, the burden is on the agency to prove why regulations should be made," he said.