The need for speed is making its way to downtown’s parking system.

A plan to convert four Massachusetts Street parking meters per block into 15-minute in-and-out meters won preliminary support from city commissioners Tuesday evening.

A majority of commissioners sided with a group of about 40 merchants who had signed a petition supporting the change.

“There are an awful lot of businesses that would benefit from this, and consumers are going to benefit too,” said Bob Schumm, owner of Buffalo Bob’s Smokehouse and Dynamite Saloon.

The in-and-out parking will benefit take-out restaurants, jewelry shops that offer repair services, flower shops, clothing alteration businesses, banks, and several other types of service businesses in downtown, commissioners were told.

“I’d be willing to try anything that helps people get in and out of the spaces quicker,” Commissioner Mike Dever said. “That is what we’re trying to promote.”

Commissioner Mike Amyx expressed concerns about the proposal, saying it would frustrate potential shoppers and visitors to downtown who are used to all the meters on Massachusetts Street being two-hour meters.

Each block on Massachusetts Street downtown has an average of 37 parking stalls on each side. The proposal would convert two stalls on each side of Massachusetts, from Sixth to 11th streets, into 15-minute meters. Commissioners directed staff to bring back a more formal plan for how the special meters would be marked, and exactly where they would be placed on each block.

Commissioners also tentatively agreed that the special meters should have a fee of 25 cents for 15 minutes, which would be double the rate charged at the two-hour meters. But commissioners declined to charge a special fine for overtime parking at the short-term meters. It will be $3, which is the same for all downtown meters.

If commissioners give final approval in the next few weeks, it will take about two months to convert the parking meters. Commissioners agreed to revisit the issue in about a year.