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1967 Ford Mustang Shelby GT500 - Eight Barrels Of Fun
Nothing says Mustang muscle car better than a '67 Shelby GT500's dual-quad 428
Nothing says Mustang muscle car better than a ’67 Shelby GT 500’s dual-quad 428. The idle is lumpy, the clutch is stiff, and the exhaust is loud. Just the way I remember Mustang musclecars in the late 1960s.
Marc Crocker’s survivor ’67 GT 500 is exactly the sort of Shelby you might have seen at the local drive-in in 1969—slightly faded Acapulco Blue paint with a few nicks here and there, big-block headers poking into view below the rocker panels, and an odometer showing 54,000 miles and change. The 46 year-old unrestored fastback looks out of place among the concours Shelbys in front the Marriott Tulsa Southern Hills hotel, but its patina attracts the majority of finger pointing and stares.
In what has become an annual occurrence during the Mid America Ford and Shelby Nationals in Tulsa, Oklahoma, event founder Jim Wicks arranged to put me in the driver’s seat of a survivor Mustang musclecar. Over the past five years at Tulsa, I’ve driven a 21,000-mile ’70 Boss 429, a 51,000-mile ’65 GT 350, a 10,000-mile ’68 GT 500KR convertible, and a 68,000-mile ’66 GT 350. This will be my first chance to stick my right foot into the eight barrels of fun that reside under the ’67 Shelby’s fiberglass hood.
When the 390 FE found its way into the Mustang for ’67, Shelby American upped the ante by equipping its first big-block Mustang with a Police Interceptor version of the 428. And just as the GT 350 name had nothing to do with cubic-inches or horsepower, Carroll Shelby christened it the GT 500. “It sounded bigger than anything else out there,” Shelby explained. The ploy worked—Shelby American produced 2,044 regular-production GT 500s, compared to 1,135 GT 350s.
In Shelby’s “more is better” fashion, the standard 428 PI’s four-barrel induction was replaced by a pair of 600-cfm Holley four-barrel carburetors on an aluminum medium-rise intake manifold. Ford’s progressive linkage allowed normal two-barrel operation at low speeds; around half-throttle, the primary barrels on the second carb opened. At wide-open throttle, the vacuum secondaries on both Holleys popped open, providing the 428 with 1,200-cfm of air flow.
Somehow, Shelby American got away with Ford’s 355-horsepower rating. According to the Shelby American Automobile Club’s ’65-’67 Shelby Registry, the true rating was more like 400.
For Crocker, owning a survivor Shelby is an “awesome” experience and a dream come true. “My father bought a new ’66 Mustang and I grew up reading the Mustang Recognition Guide,” he explains. “I love survivor cars because I like seeing how they were originally built and how they actually drove back in the day.”
Crocker found his ’67 GT 500, Shelby VIN 67400F0A02505, several years ago, purchasing it on the “Shelby payment plan” from its previous owner on the east coast. “It took me several years to pay it off so it was nice to finally take delivery in February 2012,” Crocker explained. “I was specifically looking for an unrestored, original Shelby that had been built at Shelby American in southern California before production moved to Michigan.”
Per its listing in SAAC’s Registry, 02505 was built at Shelby American’s LAX facility on July 24, 1967, and shipped to Robie Ford Sales in Dorchester, Massachusetts. The first known owner was Christopher Pina. It then passed through a succession of Massachusetts owners and spent two years in Georgia before returning to Massachusetts in 2008. The reason for the low-mileage is unknown.
At some point in the car’s past, a previous owner installed a fairly wild camshaft, tubular headers, and a set of digger gears, estimated at 4.10:1 by Wicks. The Flowmaster mufflers imply a more recent modification, perhaps as replacements for a blown-out pair of glasspacks.
For detailing and to assure safety and reliability on the highway, Crocker delivered the GT 500 to Randy Roberts at Muscle Car Restoration for engine and electrical work.
And now Crocker’s big-block Shelby awaits me in front of the Tulsa Marriott. Wicks arrives with the keys for a quick “get acquainted” drive, warning that there’s a rattle in the exhaust system “but it’ll go away once you get moving.” The 428 fires on the first twist of the key, igniting a ferocious, barely muffled idle that turns heads from anywhere within earshot. The clutch is stiff, an obvious indication of a performance pressure plate. The older Hurst shift is well-worn and it takes a few efforts to get the chrome-plated lever into Reverse instead of First. Pulling out of the tight parking spot, I notice that the power steering is typical of the 1960s with so much assist that you can easily spin the steering wheel with your little finger.
The Shelby’s tach doesn’t work, so I can’t determine the idle rpms, but the engine idles fast enough that very little throttle is needed to get the car underway. The low rear end gearing helps too. After a few shifts, I get accustomed to the release and feel of the heavy-duty clutch.
I’m happy for the test run opportunity because a couple of my previous survivor rides in the Tulsa heat have resulted in pegged temperature gauges and even spewing green coolant. But Crocker’s 428 Shelby doesn’t seem to mind the slow city traffic and long periods of idling at stop lights. The temp needle hovers just to the left of the halfway mark between “C” and “H.”
During the stop-and-go of Mid America’s evening cruise to the downtown Brady Arts District, passenger Mark Storm and I peruse the Shelby’s Deluxe interior. All of the Shelby equipment is present and accounted for—roll bar with safety harnesses, wood-rimmed steering wheel, and underdash pod with oil pressure and amp gauges. With the windows down in the Oklahoma summer heat, the exhaust noises, including the “ticking” from the headers, ricochets off nearby buildings and tall curbs; the sound of the hot-cammed 428 is so sweet that I never even think to try the AM/FM radio.
With 800 cars participating in the police-escorted cruise to downtown, there’s no chance to punch into the second Holley. However, returning from downtown, we take an outskirt expressway to escape the city traffic and stop lights. The Shelby romps to 60 mph easily, the engine screaming at an estimated 3,000 rpm (remember, non-working tach). It’s finally time to check out full-throttle, so I ease into the pedal. There’s a little notch you can feel about half-way into the throttle travel. Before the notch, the 428 feels like any other FE big-block—good power, lots of torque. After the notch, the second four-barrel’s primaries open and the Shelby rockets ahead with a vengeance as the vacuum secondaries on both carbs come into play. The torque is impressive; no need to down-shift, even at slower speeds in Fourth gear.
A red light with no traffic ahead provides the perfect opportunity to see what the Shelby will do from a standing start, but I don’t have the nerve to floor it in First gear, and likewise expect tire spin when all eight butterflies finally slap open in Second. However, the older BFGoodrich Radial T/As have plenty of grip left in them, although they emit a hearty “chirp” on all three upshifts.
It’s exactly what you’d expect from a 428 big-block with eight-barrels of wide-open Holley.