1st Mustang GT350, GT350R roll off Flat Rock line

The first production Shelby GT350 and GT350R Mustangs rolled off the assembly line Thursday at Ford Motor Co.’s Flat Rock Assembly Plant. The performance pony cars will hit showrooms this fall.

They’re powered by a 5.2-liter flat-plane crankshaft V-8 that will get 526 horsepower and 429 pound-feet of torque.

It will be Ford’s most powerful naturally aspirated production engine ever.

The GT350R is a track-ready but street-legal performance car that drops a number of amenities, like air conditioning, in the pursuit of reducing weight.

Ford does offer an electronics package that does include some of those amenities.

There will be a very limited number of 2015 model-year cars: 100 GT350s and 37 GT350Rs.