Two out of every five Americans expect within the next few years that they will have to change the transportation method they use because of the energy crisis, according to a nationwide survey.

If changes are necessary, Americans want to exercise options ranging from more carpooling to better public transit rather than being forced to gasoline rationing, higher gasoline taxes or restrictive downtown parking policies, the survey says.

The survey, by Hart Research Associates, was released by Transportation Secretary Brock Adams Friday. Its release coincides with a major legislative debate between the administration and the House Public Works Committee on how much money will be available for future highway and transit programs.

Peter Hart, who supervised the $54,000 survey, called it the first compreshensive look at American attitudes on transportation in a decade. Among the things learned:

Three out of five Americans think that there are enough interstate highways. Two-thirds of those surveyed think there are enough major and minor road generally.

More than half of those questioned (54 percent) think there should be more buses and almost half (46 percent, think more money should be spent to buy them.

One American in five favors more commuter rail or subway systems, and the same number thinks more should be spent on such systems.

Amtrak is supported by more than half of those surveyed, even though only 11 percent of those questioned had ridden a train within the past five years.

Hart said the survey showed that "the people who are going to change (their transportation habits) are under 35. People over 50 have determined their lifestyles and transportation. You will not see them on public transportation or in car pools."

Indeed, half of those between 25 and 34 years of age said they "expect change" in their personal transportation within a few years, but more than half of those between 50 and 64 said they expected no changes.

If changes are necessary, the most favored option (53 percent) was strict enforcement of the 55-mile-per hour speed limit. The least favored (51 percent) was gasoline rationing.

Adams expressed surprise at the relative acceptance of buses and carpools as transportation options, especially since the survey was nationwide in scope and did not focus on transit-heavy urban areas.

According to a departmental analysis of Hart's findings, "fringe parking linked with buses or rail lines, special bus lanes and door-to-door bus service all were favored."

Adams said the survey, compiled from 1,538 interviews in December, was part of the basis for his legislative proposal for highways and mass transportation.

The proposal includes a deadline for the states to decide whether to complete their interstate highway systems and purports to remove the financial advantage highway programs have over other transportation programs. That advantage comes because interstate projects receive 90 percent federal assistance while transit programs received 80 percent.

Regardless of where the money goes, however, there is little of it, according to critics of the legislative package. The American Public Transit Association, which represents the nation's metropolitan bus and rail systems, has labeled the bill "retrogressive."

Rep. James J. Howard (D-N.J.) recently completed hearings on the administration proposal in his Public Works subcommittee on surface transportation. A draft subcommittee bill, which will be debated after the Easter recess, includes a total of $20 million more over a four-year period than does the administration bill. It also has bout $1 billion more per year for public transportation.