The chairmen of eight House committees and subcommittees asked the White House yesterday not to rush ahead with a controversial new executive order that could make more government records secret.

The proposal, which also would wipe out existing rules encouraging declassification after 20 years, was submitted to selected congressional committees last week for review by Feb. 22.

Leading members of House committees and subcommittees on Science and Technology, Agriculture, Foreign Affairs, Government Operations, the Judiciary and Intelligence protested in a joint letter that they needed more time in view of the scope of the proposed changes.

"The classification rules affect not only the executive branch and the Congress but also the scientific, industrial, research and academic communities," they said in the letter to White House national security adviser William B. Clark. "No change should be made . . . without allowing for thorough review."

Under President Carter's 1978 order on classification of national security information, and an earlier one promulgated by President Nixon in 1972, it has been a basic rule that material should not be classified if there is a reasonable doubt about the need to do that.

Under the White House draft of the Reagan order, the new rule would be: when in doubt, classify.

The 40-page draft apparently would permit the classification of "basic scientific research information," which the Carter order prohibits. The draft also would authorize government officials under certain circumstances to "reclassify" information that has already been declassified.

"I'm not sure the public is aware of how sweeping it is," said Rep. Glenn English (D-Okla.), who took the lead in submitting the letter as chairman of the House Government Information subcommittee. "Without question, it is going to reduce the availability of information to the public."

A study by Morton Halperin and Allan Adler of the privately funded Center for National Security Studies contends that the new order, which the president can promulgate on his own, also would effectively amend the Freedom of Information Act without congressional approval.

Under the Freedom of Information Act, national defense and foreign policy information that is "properly classified" is exempt from disclosure.

The proposed executive order, the study says, would add "broad new categories" of information that can be classified, such as data concerning the "vulnerabilities or capabilities of systems, installations, projects or plans relating to the national security."

Robert Lewis, a spokesman for the Society of Professional Journalists, complained in a letter to the members of the House and Senate Intelligence committees that, read broadly, "that could include, for example, all computer operations and telecommunications."

According to a legislative aide who attended a briefing on the draft order, the administration's basic pitch is that the language of the order is "very broad" not because it plans to classify that much more information, but because it wants to keep the courts from questioning the actions of the executive branch.

"What they're really saying is 'Trust us,' " this aide said.

Steven Garfinkel, who as director of the executive branch's Information Security Oversight Office has been involved in drafting the order, also reportedly told at least one group of staffers that the administration wants to add the Environmental Protection Agency to the list of agencies with classificatiion authority, so that it can protect documents dealing with issues such as "acid rain in Canada." Garfinkel was unavailable for comment.