Ford Shelby Mustangs engineered for street and track | North County Ford Vista CA

2015 Ford Shelby GT350, GT350R go on sale this fall. Michigan plant running prototypes down the line now.

Developing the new Ford Mustang was tricky enough, but engineers knew it had to be capable of spawning extreme performance Shelby versions as well.

It wasn't easy, said Dave Pericak, Ford Performance director. It became clear there would still be some additional investment needed down the road to pull off performance versions that can tear up a track.

Ford unveiled the Shelby GT350 Mustang at the 2014 Los Angeles auto show last November. In January, at the North American International Auto Show in Detroit, the automaker showed the Shelby GT350R which is a stripped down, lightweight, street legal, track version. They go on sale this fall.

Ford's performance team is confident the two new cars are deserving of the Shelby name while still engineered so they could roll off the same assembly line in Flat Rock, Mich., as the conventional Mustang. A limited amount of special tooling was needed, even though the Shelby Mustangs have a different look, starting with the face, and changes to the chassis, suspension and brakes to handle the speeds and demands of a track car.

Ford has started building early prototypes in Flat Rock. The Shelby Mustangs "stick out like a sore thumb on the production line," said Adam Wirth, suspension, wheel and tire supervisor. And assembly is interesting, especially the GT350R that can be ordered so stripped down it does not even have air conditioning or a radio.

Everything is on track to start taking dealer orders in about a month for delivery this fall, Pericak said.

Pricing will be announced soon for a car that will compete against everything from a Chevrolet Camaro Z28 to Porsche 911 and Nissan GT-R.

All dealers are eligible to sell the Shelby Mustangs but there are not a lot to go around. Ford will only build 100 Shelby GT350s and 37 GT350Rs for the 2015 model year which is the 50th anniversary of the original Shelby GT350 that jump-started the pony car wars of the 1960s.

For the 2016 model year, volume is expected to be in the 4,000-6,000 range, said Jim Owens, Shelby marketing manager.

So why build such a niche vehicle?

"Ford Performance is a money-making business," said Eric Zinkosky, suspension and vehicle dynamics technical specialist. These exclusive vehicles are scooped up by discriminating buyers.

The 2015 Shelby GT350 has a naturally aspirated 5.2-liter V8 with a flat-plane crankshaft which gives it a different firing order for more high-revving power and powerful exhaust sounds. It puts out more than 500 horsepower and more than 400 lb.-ft. of torque. It has a six-speed manual transmission.

It even has unique tires of a special compound developed by Michelin.

"You don't have to be on a track to enjoy this car," said Wirth.

Some owners might never take their GT350 on the track — but they know they could, said Owens. Others might never take their GT350R on the road or even get a license plate, preferring to trailer the car to the track.

Key to making it a stiff performance car on the track but still comfortable on the street is Ford's first use of MagneRide suspension dampers that adapt to the road under it. It can even handle driving over a curb, said Brent Clark, vehicle dynamics supervisor.

General Motors has used the MagneRide damping system extensively for the Chevrolet Corvette and the Cadillac brand. Ford developed its own continuously variable damping system for its Lincoln brand but for the Mustang, Ford needed a system that reacted even faster to drive conditions.

The Shelby duo have the most powerful brakes on a Mustang to date. "It's the real secret to making this car fast," said Zinkosky, knowing they will control the speed heading into a corner.

Ford has said it will introduce 12 new performance vehicles by 2020. Among them are the Ford GT due in the second half of 2016 — Ford will make 250 a year — as well as the Mustangs, Focus ST, Focus RS, Fiesta ST and F-150 Raptor.