The Ford Mustang GT-R was the pony car's anniversary gift to itself

The Ford Mustang is about to turn 50. This means that one decade ago -- and please check our math here -- the Mustang was about to hit 40. The Blue Oval celebrated in style. Extreme, 440-hp side-pipe-wearing style. The result was called the GT-R (not that GT-R, silly) and it was one very mean, very orange demonstration of what the folks at Ford can come up with when you give them a bin of go-fast bits and a mandate to prove what the Mustang is capable of.

Sure, the GT-R's overall shape is immediately recognizable as the retro-inspired fastback-bodied shape the car has worn since the 2005 model year. But there's not much stock 'Stang on display here, as we make clear in the April 19, 2004 issue of Autoweek. To start, the car's 4.6-liter V8 was bored out to a magical five liters. Heads were ported, cams are of the high-lift aftermarket variety, gasoline is supplied by high-flow fuel injectors.

Headers are custom, leading to exhausts that emerge just ahead of the rear wheels. We're sure those 4-inch pipes sound wicked. Brakes and suspension get reworked, too. There's a roll cage to keep you safe from yourself if you take the car out on the track. And it's orange -- very, very orange -- a color set off by swaths of black carbon fiber.

Many of the parts and pieces used to build the Ford Mustang GT-R were either available from Ford Racing Performance Parts (or were slated to be at the time of this writing). Thing is, you don't really need to bore out your stock motor, throw in custom cams and rip out your comfy, air-conditioned interior to get what was once crazy one-off track-car performance. Less than a decade after we ran this feature, the 2012 Boss 302 was putting down 444 hp off the lot. The 5.0-liter V8-powered 2015 Mustang is supposed to be good for "at least" 420 hp, and that's before Ford starts playing around with special editions.

Scope out the Ford Mustang GT-R below and appreciate how far we've come -- and how spoiled by performance we've become -- just 10 years after this 40th anniversary beast roared onto the scene.

Ford Mustang GT-R 40th Anniversary car

The Ford Mustang turns 50 years old during 2014; to celebrate the many lives of America's favorite pony car, we'll be posting selections from our archives. Check out our Mustang mini-site, where you'll find news, road tests, sneak peeks and even classic Mustang ads from the pages of Autoweek. We'll also have all the latest news and photos surrounding the redesigned 2015 Ford Mustang as it rolls out, so stay tuned.

By Graham Kozak