One critical piece of evidence, he said, was a memorandum written by an Oldsmobile engineer, Edward Ivey, in 1973, in which Mr. Ivey estimated that fuel-tank fires were costing G.M. only $2.40 per vehicle.

General Motors, in a statement, maintained that the car's fuel tank was safe and met or exceeded Federal standards. ''This extremely severe crash was caused by a single factor -- drunken driving,'' the company said. It said it would appeal.

Richard W. Shapiro, a Phoenix lawyer who represented the auto maker, said the verdict was ''shocking'' and noted that the jury had not been allowed to hear evidence that the driver of the other car was drunk and went to jail. He also said the company had been barred by the judge, Ernest G. Williams of Los Angeles County Superior Court, from presenting evidence showing the safety history of the vehicle and also crash-test data showing that the car's design was safer than the one the plaintiffs advocated.

The National Highway Traffic Safety Administration has conducted two safety investigations into the Malibu since the 1970's but neither involved the fuel system, said Timothy Hurd, a spokesman for the agency. He said the agency had recently notified auto makers that it was reviewing whether to tighten its rules on protecting fuel systems but that this was unrelated to the case.

But Joan B. Claybrook, who was the administrator of the highway safety administration in the Carter Administration, said today that big verdicts in personal injury lawsuits were sometimes the first signal to regulators that a problem existed. ''Could this car be a problem and N.H.T.S.A. not know about it?'' asked Ms. Claybrook, who is now president of Public Citizen, a consumer advocacy group. ''Absolutely.''

Ms. Claybrook said she first learned of problems with Ford Pinto's gas tank and ordered a Federal investigation after a $125 million personal injury verdict in 1977. That award, and another big one involving the Pinto fuel tank, was subsequently reduced substantially. But the Pinto was later recalled because of the fuel tank problem.

Mr. Panish, the lawyer for the Los Angeles plaintiffs, said there are 30 to 60 other lawsuits involving fuel-tank fires of the Malibu and other so-called A-body cars by G.M., including the Pontiac Grand Am, the Oldsmobile Cutlass and the Chevrolet Monte Carlo, which have similar fuel-tank designs. A spokesman for G.M. said that number sounded exceedingly high and that the company had lost only one other case involving fuel-tank fires on A-body cars. In that case, G.M. was ordered by a court in Fort Lauderdale, Fla., last year to pay $33 million to the victims of an accident in which the fuel tank of a Cutlass exploded, killing two people and burning four others.