Gentlemen, start your outhouses.

Langley’s Soup Box Derby, a wacky take on the venerable Soap Box Derby for sleek downhill gravity racers allegedly designed and built by kids, is around the corner and up First Street.

“We’re hoping for a big turnout,” Tucker Stevens, president of the Langley Community Club and Langley Men’s Club, sponsors of the event, said Thursday. “I hope it doesn’t rain. It rained a little last year.”

This year’s derby will be Saturday, Sept. 18. Registration and weigh-in begin at 9 a.m. at the US Bank parking lot at Second Street and Anthes Avenue.

From there, the racers will parade to the top of First Street hill for about four hours of head-to-head heats that organizers hope will end just short of a barrier of hay bales at the bottom.

Head-to-head is right, if you’re talking about Gary Piper’s racer, a one-holer commode-on-wheels carrying the numbers 1 and 2.

“I’m going undefeated this year,” a confident Piper, of Clinton, said Thursday. “There’s no question I’m going to beat everybody.”

The double-barreled mean machine entered by Whidbey Island Wines has won most of its recent heats, but everybody who races gets a trophy, Stevens said. It might even be trophies they’ve made themselves.

Festivities actually start Sept. 11, the Saturday before the race, with a trophy-making party at the Stevens’ house in Langley. He called the annual gathering “an evening of creative mayhem, with all the materials and refreshments provided.”

The Soup Box Derby is an almost-anything-goes event that dates back, with a couple of interruptions, to 1972. Currently, it boasts an eight-year run.

Entrants can be almost anything on wheels, and the wheels themselves can be from almost anything — wagons, bicycles, tricycles, roller skates, cabinet castors.

Langley metal artist Tim Leonard’s entry is made entirely of wood, including the wheels.

Racer design is limited only by the imagination, but each must have brakes, and can be no heavier than 600 pounds, 300 pounds for those of drivers 12 and younger.

Each vehicle can carry as many as four people, but all drivers and passengers must wear helmets and sign injury waivers, Stevens said.

As many as 33 vehicles can enter, Stevens said, but he can’t remember where that number came from. Last year there were 20 entrants; in 2008 — the year of the deluge, the year 86-year-old poet Peter Lawlor raced and crashed the coffin he said he planned to be buried in — there were 14 entrants.

Through the years, the entry fee was $30, until last year, when all but $5 was waived in deference to the miserable economy. This year, the fee is $25, Stevens said, even though he admitted the economy is still miserable.

All proceeds go to local charities and to beautify the city, he said.

The race begins at the top of First Street hill, near Park Avenue, and runs down the steep incline for a long block or so.

Following the race, volunteers will whisk away the hay bales stacked along both sides of the course and at end of the run, along with banners and all other paraphernalia associated with the event.“It’s amazing how it all goes up, then all comes down,” Stevens said. “It looks just like nothing happened.”

There will be no official post-race party, he added.

“People mostly just go home,” he said.

Piper, the Langley real estate mogul, has entered his outhouse-on-wheels named “Hurry” for the past six years. Its license plate reads “Island County Health Department IM4U2GO.”

Piper said he lost every heat at the beginning of his derby career, until he added 100 pounds of steer manure to the back axle.

That year, he won one race. This past year, he added another 100 pounds of manure and won three races — “and had a hard time stopping.”

“Now it’s just about right,” Piper said. “It was very wobbly at first, but more weight on the back made it fast and true.

“I also painted flames on it,” he added. “Now it’s way faster.”

Meanwhile, Stevens, 70, and his son Jason Sarff, 32, of Kent, plan to enter their three-wheeler again this year. Sarff plans to drive the funky tricycle with three bicycle wheels and hand brakes.

“It’s kind of triangle-shaped, and has all kinds of bells and whistles,” Stevens said. “I call it the ‘City of Langley.’ My wife says this is the last year it can stay in the yard.”

Although he won the race one year with a garbage can on wheels, Stevens said he has no previous race-car-driving experience, except for the drag racer he and eight of his high school buddies took turns jockeying back in the day.

He said he also did some motorcycle racing in his younger years, and was an avid surfer. But he rarely pushed the envelope then, and doesn’t plan to start now.

“When something became dangerous, I always backed off and went on to something else,” Stevens said.

But nonetheless, he’s full of anticipation for his “ceremonial” dash down First Street before the official race begins.

“Believe it or not, the adrenalin comes right back,” Stevens said. “All of a sudden, you just go ‘Wow!’”

Registration forms for the race are available at Langley City Hall and the Langley Chamber of Commerce office.

For more information about the Derby on Sept. 18, or the trophy-making party on Saturday, Sept. 11, call Stevens at 221-4188.