March 7, 1986

When the Armada Corporation lost its directors' and officers' insurance earlier this year, causing 8 of the 10 members of the board to resign, the Detroit-based manufacturer of alloys and exhaust systems set a special requirement for the replacement candidates: they could not be too rich. The company reasoned that if the directors were sued, and had to pay damages out of their personal assets, Armada could afford to indemnify them only if they did not have many assets. Armada is not the only company having insurance problems these days. Because of increased litigation, larger court awards and a rapidly shrinking pool of available insurance, many companies can no longer find, or afford, insurance for their directors and officers. Without insurance coverage, executives and board members may be held personally liable for paying damages to shareholders and others who are harmed by corporate actions.

The Cuomo administration today proposed a series of changes, the first in more than a decade, in the Rent Stabilization Code, which governs nearly a million apartments in New York City. A 73-page document, drafted by the State Division of Housing and Community Renewal, was greeted by criticism from landlord and tenant groups alike. It will be subject to public review at hearings in Manhattan in April before the housing agency completes a final draft and puts the code into effect. No legislative action is needed. The rules would not apply to the city's 218,000 rent-controlled apartments, which are governed by a separate code.

Friday ANTIQUES FOR BROWSING Browsers and collectors who have recovered from all the other antiques shows in the last few months and are beginning to sniff around again may perk up at Sanford Smith's Armory Antiques Show this weekend. Seventy-five exhibitors from all over the country as well as England, France, Sweden and the Netherlands will be on hand to display items that range from classical antiquities to Art Nouveau and Art Deco. There will be folk art and quilts, American Indian art, Chinese and Japanese works, American and English arts and crafts and more. The show is open from noon to 10 P.M. today and tomorrow and from 11 A.M. to 6 P.M. on Sunday at the Seventh Regiment Armory, at Park Avenue and 67th Street. Tomorrow, there will also be an all-day symposium from 9 A.M. to 4 P.M. on American painting with an agenda that includes lectures on taxes and insurance, today's market and restoration and conservation, along with a round-table discussion by dealers who will answer questions from the audience. Admission to the show alone is $6. The $60 price tag for the symposium includes lunch and admission to the show. Information: 249-8575. TRUFFAUT'S 'ENGLISH GIRLS' Devotees of Francois Truffaut may be interested in re-evaluating his 1971 film ''Two English Girls,'' which opens today at Cinema Studio 2. Before his death in 1984, the director reassembled the film, restoring excised footage and completing his own vision of the work.

New York City will increase the number of vehicles it tows, institute wide use of the restraining device known as a boot, and target the ''heavy hitters'' among scofflaws under a new plan to collect parking fines, Mayor Koch said yesterday. But the new effort, part of a reorganization of the Parking Violations Bureau, will also temporarily suspend the use of private agencies to collect parking fines, he said. Mr. Koch said the city would step up its own collections before deciding whether to rehire the private agencies, some of which have reputedly paid city officials bribes in exchange for continuing their contracts. ''We're going to see what it is that we can do to a greater extent in-house, without foreclosing going back to collection companies under different terms, under different conditions and maybe with different companies,'' the Mayor said at a City Hall news conference.

The Pioneer Corporation, a diversified energy company with sizable natural gas reserves but several struggling operations, said today that it had approved a merger offer from Mesa Limited Partnership, an energy concern headed by T. Boone Pickens. Under the offer, Pioneer shareholders will receive a new form of Mesa securities called preference units. The merger was valued at between $763 million and $830 million. Analysts said the purchase was consistent with Mr. Pickens's strategy of acquiring proven energy reserves rather than investing in exploration for new reserves. They added that the pact would increase Mesa's total natural gas reserves by more than two-thirds, to 2.1 trillion cubic feet. Natural gas accounts for nearly 90 percent of Mesa's energy reserves.