General Motors will be showing this Chevrolet Camaro Hot Wheels show car, which also appeared at the Specialty Equipment Market Association (SEMA) trade show.Photo credit: Richard Truett

The engine in the dark gray Chevrolet Camaro COPO being backed out of a transporter this morning in a parking lot just north of Detroit sounded like a machine gun every time the driver revved the engine.

It’s one of a dozen or so custom, low-production, concept or otherwise rare Camaros that General Motors trucked out to famed Woodward Avenue here in preparation for this weekend’s Woodward Dream Cruise.

The annual event usually draws more than 1 million people and around 40,000 classic cars to a 22-mile stretch of four-lane road running from Detroit’s city limits north to Pontiac, Mich.

Detroit automakers will display their high-performance hardware in a bid to outmuscle one another and get or stay on shopping lists.

With the Ford Mustang and Chevrolet Camaro locked in a tight sales race — Camaro is leading by 1,402 units through July — just about every permutation of both cars will be on display.

Ford is building a shrine to the long-running sports car by renting an entire street in Ferndale, just north of Detroit, and renaming it “Mustang Alley.” Ford also will display its trucks and other sporty cars, such as the Focus and Fiesta ST models.

Chevrolet will attempt to pump up early orders for the all-new 2014 Corvette by showing off the Stingray just up the street in Birmingham.

Chrysler Group rented a shopping center parking lot and will fill it with classic cars from all its brands, as well as the new version of the Viper and the Dodge Challenger sports coupe, which has registered a 25 percent sales bump so far this year.

Chrysler is debuting a performance-oriented concept Ram truck Saturday at 10 a.m., marking the first time an automaker has used the Dream Cruise to debut a concept vehicle.

“If you consider the location and the hot spots for auto enthusiasts, the Dream Cruise ranks at the top,” said Chrysler spokesman Nick Cappa. “What better place to reveal a vehicle that will be appreciated by its audience?”

The Detroit 3 are staffing their venues with product specialists who will answer technical questions from the public. Automakers view the event as a way to build brand loyalty by offering personal interaction with the engineers and designers who created the vehicles.

“Many of the product development specialists do know more than the average salesperson,” said Paul Brearey, Ford’s marketing manager for consumer events. “But there’s no pressure to buy anything. We’re not trying to sell them a car, and that makes people more comfortable,” he said.

Hyundai spokesman Miles Johnson said the Dream Cruise is not really the right venue to showcase the Korean automaker’s sporty vehicles, such as the Veloster. In years past Hyundai has had a presence at the Dream Cruise, showing off its sporty cars, but it decided to pass this year.