Senate Finance Committee Chairman Bob Packwood (R-Ore.) yesterday released a list of 175 tax breaks for companies and projects that would be protected in his panel's tax-overhaul bill, and Sen. Howard M. Metzenbaum (D-Ohio) vowed to make an issue of them Monday when the bill comes up on the Senate floor.

The beneficiaries include Pan Am World Airways, the New Orleans Superdome, the Houston Astrodome, General Motors, Toyota, Goldman Sachs, RCA, MCI, Phillips Petroleum, Federal Express, the University of Delaware and most steel companies.

Those named on the list are subjects of the tax bill's numerous "transition rules," a standard feature of tax legislation designed to ease certain groups into a new tax system. For example, while the bill would repeal the investment tax credit and some tax-free bonds, certain projects on the list would be allowed to retain those benefits.

The exceptions would save their recipients $5.5 billion in taxes over five years, according to congressional estimates. By comparison, transition rules in the tax bill passed by the House last year would cost more than $25 billion.

All projects on the list were under way when the Finance Committee bill was approved, but Metzenbaum argued that other projects in similar stages were not treated equally. The exceptions disproportionately help interests in the home states of Finance Committee members, but about half would aid projects in other states.

Among the beneficiaries close to Washington are a rapid-rail line to Dulles International Airport that would retain existing tax favors for its bondholders and its capital investments, and Baltimore's Harborplace, a real estate development, which would keep its generous depreciation write-offs.

The language of the tax bill generally camouflages the beneficiaries. For example, the Dulles rail line is described as "a mass commuting facility that provides access to an international airport" and for which "a corporation was formed . . . in September 1984" to handle construction.

General Motors is described as "an automobile manufacturer that was incorporated in Delaware on October 13, 1916." A drilling project by Sonat, a natural resources firm in Alabama, is described as the result of "a binding contract entered into on October 20, 1984, for the purchase of six semisubmersible drilling units."

The vague language prompted Metzenbaum to charge at a news conference earlier in the day that "there is blatant concealment in this bill . . . an effort to hide special provisions." Hours later, Packwood handed Metzenbaum on the Senate floor the list of beneficiaries of the transition rules.

Metzenbaum commended Packwood for his "forthrightness," but an aide said last night that the Ohio Democrat likely will seek to repeal many of the exceptions through amendments. Sen. David H. Pryor (D-Ark.) said earlier that he would seek to defeat a transition rule that would mean $500 million for steel firms.

Sen. William V. Roth Jr. (R-Del.), a Finance Committee member, said he also will seek the repeal of certain transition rules in hopes of using the money to preserve deductions for all contributors to Individual Retirement Accounts.

"It will be very difficult to explain to the taxpayers that they have to give up their IRA deduction while the tax breaks for defense contractors and steel companies remain intact," Roth said.