The speed limit along upper State Street in Brewer is typical of most intown byways – 25 miles per hour.

But 73 drivers hope to get away with a little speeding Saturday, in Soap Box Derby cars that reach speeds of up to 28 mph.

Opening ceremonies for the Eastern Maine Soap Box Derby are scheduled for 8:30 a.m., with heat races to start at 9, according to race director and EMSBD president David Vroom of Bangor.

Races will continue throughout the day, with final heats expected to start about 4 p.m.

State Street will be closed beginning at 6 a.m. Saturday, Vroom said.

Preregistrations are down slightly from a year ago, when 86 drivers took part in an effort to qualify for the All-American Soap Box Derby in Akron, Ohio, which will be held this year on July 26-31.

“Because we have a few less preregistered, this year we’ll be able to offer double-elimination competition, so all the kids will have a minimum of four runs,” said Vroom.

Races will be held in Stock and Super Stock divisions that utilize cars assembled from kits, and a Masters division in which participants build vehicles according to Soap Box Derby guidelines.

“The [Masters] cars have a look like the older-style cars, and kids are able to learn to use some tools as they’re building them,” said Vroom, one of about 40 volunteers involved in conducting the event.

Stock and Super Stock participants must be at least age 8 and no older than their 18th birthday on race day. Masters division racers must be at least 10 and no older than their 18th birthday, Vroom said.

There’s also a Super Kids division involving special-needs youths riding in specially made two-person cars with former Soap Box Derby participants. The top finisher in that division also will earn a trip to Akron.

Most participants took practice runs last Saturday on the State Street course, which takes approximately 43 seconds to complete, Vroom said.

The Eastern Maine Soap Box Derby is one of four regional derbies held in Maine. The Southern Maine derby was held last weekend in Rumford, with Cody Douglass of Turner (Stock) and Taylor Bartlett of Poland (Super Stock) qualifying for the 67th All-American Soap Box Derby.

The 10th annual Midcoast Maine Soap Box Derby in Camden and the ninth annual Northern Maine Soap Box Derby in Houlton are both scheduled to be held June 26.