Ignoring the sirin song of Proposition 13, Houston voters solidly approved a tax increase Saturday to create a modern bus system - a move seen as crucial to the growth of the nation's premier boom town.

The action comes as large corporations have begun turning away from locating here because of the city's Gordian knot of traffic, and as federal air pollution standards threaten industrial growth if automobile fumes are not reduced.

Approval of the sales tax increase, which will bring in $1.3 billion over 10 years, came after a well-financed and slick advertising campaign supported by many of the city's biggest corporations, firms and catchall business ventures.

Mayor Jim McConn attributed much of the victory to mewcomers here who previously lived in cities with good mass transit. It was these newcomers - adding about a thousand people a week - whose cars helped create today's traffic problems.

More than 2,000 cars have been added weekly to a highway system that has not grown significanily since 1973, when a mass transit proposal was routed.

Opponents had hoped to mine the mother lode of antitax, antigovernment sentiment in the nation illustrated by Proposition 13, a property tax-cut measure approved in California. But the tax burden here, about the lowest in the nation, is nowhere near California's, and Texans still have a frontier attitude of doing whateven is necessary to keep expanding.

And traffic had already taken a toll on a metropolis that aspires to be the city of the future, to be in the 21st centruy what New York was in its heyday. Politicians and business, and transportation and urban experts generally agreed that the continued growth in job and income here in large part is tied to better mass transit.

The influential Chamber of Commerce saw the outcome as a vote for "increased mobility and continued prosperity."

In rather light voter turnout, the transit referendum was approved by 57 percent. It creates a metropolitan transit authority that will raise the sales tax from 5 to 6 percent, a onecent-on-the-dollar tax to subsidize public transit.

The vote also was a striking and instructive display of the ballot box power of the Mexican Americans. Sixty percent of the Hispanics who voted favored the referedum, according to sample precincts.

What the Mexican-American community, and other minorities, got in return was the promise of better transit - and offical assurances of minority hiring by the new transit authority and awarding of transit comsturction contracts to minority firms. The city's major black political organization endorsed the referendum just after the city council approved a longdelayed measure to assure minorities a share of city contracts.

The city's genuine "rednecks" not the chic, weekend set that likes to dress down like rednecks voted over whelmingly against the issue, according to other sample precincts.

The referendum abolishes a city-run bus system that is so inadequate that an increasing share of the Houston workforce relies on automobiles to get to work despite extensive efforts to get workers into carpools, van pools and buses. The city has 440 buses serving its 540 square miles, an area the equivalent of Boston, Denver, Atlanta, Louisville, Detroil and San Francisco combined. (Washington has 1,800 buses, and the subway.)

Replacing this will be a metropolitan transit authority that is expected to run for Houston the kind of bus system most cities have offered for decades: a fleet that will grow by 1,000 buses in 10 years and use priority bus lanes, offer park-and-ride facilities and begin with overhead busways that later could be adapted to accommodate automated mass transit vehicles.

Joining in Houston's approval, and thus in the metro bus system, were six small cities and two incorporated areas in surrounding Harris County. The 17 cities and three other areas that voted it down can join later, but for now will neither levy the transit tax nor share in any bus service.

The referendum had been opposed by many communities unsure of how they would benefit. Some groups view the sales tax as exacting an unfair share from lower-income people, although the tax is not levied on food or medicine.

At work in favor was the fact that the added tax is earmarked to solve a problem most commuters suffer twice a day. In five years, rush hour has doubled in length, rush-hour speeds have decreased by more than a third and, if current trends continue, projections show that one commuting trip into downtown someday will take more than 12 hours.

Proponents also pointed out that the transit system will share in hundreds of millions of dollars in federal subsidies. Some people called it hypocritical to use that argument as a selling point while at the same time decrying federal spending.