Modified Mustangs & FordsFeatured Vehicles
1967 Ford Mustang GTA - The Day The Earth Sped Up
When 390 cubes aren’t enough, go bigger
Detroit’s Big Bang theory formed our automotive reality in the ’60s--at the same time, Ford, GM, and Chrysler came to the realization that bigger engines in smaller cars had the power to reduce the laws of physics like gravity, inertia, and motion to mere flies on the windshield of their hell-bent-for-leather marketing freight train. Lightweight ponycars could now be had with 390s, 396s, and 383s, allowing above average car nuts to dramatically expand their personal performance universe.
The ’67 Mustang before you is one such example. Only this car takes the Big Bang concept up several notches. This was originally a pristine example of Ford’s 320hp, 390-powered ponycar. No slouch in its own right, but that was then. Now, it has a 600hp, 484ci FE packing more punch than most asteroids of equal size and weight.
The current owner, Tony Samples, is a retired fabricator and shop manager for the aerospace industry. As you might imagine, his enthusiasm for mechanical detail is all encompassing. That would also explain how this car went from a casual rebuild project to the outer limits of what might be called "restosupermodification." Despite this Mustang’s clean and stock-looking exterior, there is hardly a system or part underneath or inside that hasn’t been lovingly massaged, refurbished, upgraded, or otherwise improved to match Tony’s vision of the perfect big-block ’67 Mustang.
This genuine S-code 390 GTA Mustang spent its entire life in the car-friendly climate of Georgia. When the original owner passed away, this machine found itself retired and parked in his brother’s garage for 20 years. It was about that time when Tony discovered it and made it his mission to buy the car.
Tony’s job one was creating a modern FE engine that continued the car’s historical ties to its original S-code heritage. Digger Don of Don Dixon’s High Performance engines (Norcross, Georgia) got the nod for the build that started as a new 427 Genesis side-oiler block and was stroked to 484 cubes. An Eagle crank and H-beam rods anchor the rotating mass. A pair of aluminum Edelbrock Performer heads were ported by Jentzen Porting Service and offer up a 10.5:1 compression ratio.
This engine hosts a Crane solid roller cam and roller rockers, in addition to assorted valvetrain components of the same brand. An MSD and a forged aluminum-cased distributor send the spark to all parties involved. An 870-cfm Holley feeds the beast, while exhaust chores were given to a custom set of Tri-Y headers, Spintech mufflers, and 3-inch exhaust tubing. The nicely detailed 427 FE-based 484ci powerplant looks like it was installed by Carroll Shelby’s crew, although Lockheed’s Skunk Works might be closer to the fact.
With 600 lb-ft of torque on tap, Tony opted for a heavily fortified Performance Automotive and Transmission Center (Bossier City, Louisiana) AOD four-speed automatic to give his forward motion some extra snap. This transmission was set up to perform without any electronic intrusions, including no converter lock-up. It utilizes a 2.84:1 First gear ratio and an 0.63 overdrive. The converter is an 1,800-rpm-stall unit. The AOD is rated for 800 hp, so Tony still has room to tweak this engine if ever inclined. A custom 5-inch-diameter driveshaft sends the power rearward.
Out back, a Ford 9-inch with 4.10 gears and heavy-duty locker are the last things the horsepower remembers as it’s spit out to the pavement. The differential is supported by a Total Control Products four-link suspension utilizing fully adjustable coilovers. The frontend stays planted with the help of Global West upper and tubular lower control arms, conventional coil springs, and adjustable shocks. Tony says his intent was to be able to readily adjust the suspension for road courses or the dragstrip. Welded-in frame connectors, a cross-braced frontend, and seam welding around the shock towers allow all these specialty suspension pieces to work efficiently.