1989–95 Thunderbird SC: Misunderstood muscle car or forgotten GT?

A big Ford Thunderbird might not be your first choice for driving eastern Tennessee’s Tail of the Dragon. The mountainous, 11-mile stretch of U.S. 129 throws more than 300 snaking curves at sports car drivers and motorcycle riders who come to “tame” it. Some don’t go home. (Don’t believe me? Google “Dragon Death Map.”)

Regardless, Kurt Kreisz recently drove his 1992 Thunderbird Super Coupe 500 miles from St. Louis—wife and three kids in tow—to experience the Dragon and other area roads. The Kreisz family joined a group of 13 other owners of T-Birds and Cougars from the 1989–97 series known internally (and by fans) as the MN12.

Powered by a supercharged V-6 and outfitted with a raft of advanced electronics, the SC was the top T-Bird and was offered through 1995. The Mercury Cougar XR7 shared the powertrain, and the FN10 platform used on the Lincoln Mark VIII is closely related. Ford built about 58,000 Thunderbird SCs; 1990 was the best sales year at just under 22,000.

Kreisz’s ’92 SC, which he bought in 1994 as a daily driver and later modified for higher performance, is one of three he owns. He also has a 16,000-mile 1990 Thunderbird 35th Anniversary Edition with a five-speed and a 1995 five-speed model with 105,000 miles. His Anniversary car was part of a special Thunderbird display at Carlisle in 2015.

Kreisz says his drag-racing SC, which has run a best quarter-mile of 11.52 seconds at 119 mph (4080-pound race weight), handled the Dragon well. He has also driven the car on three Hot Rod Power Tours.

The engine, fortified with forged internals, a different cam, Autorotor twin-screw supercharger, bigger intercooler, and custom-made headers, puts 400 horsepower to the rear wheels. Kreisz says a rear pumpkin from a 1999 Mustang Cobra, with its 3.73:1 gearing, bolted right in.

Modifying SCs is common, one reason being that they’re not worth much in stock condition. But value is not why Kreisz owns his Thunderbirds.

“There’s a niche group of us who are really fascinated by these cars. Some grew up with them,” he says. “They’re a lot of fun to drive.”

Endangered when new

Big, rear-drive American coupes were on the endangered list when the 1989 T-Bird debuted to replace its Fox platform-based predecessor. The top model in that series was the four-cylinder Turbo Coupe.

The 1989 Thunderbird was far more ambitious. At the time, the T-Bird and Cougar were the only other rear-wheel drive American cars besides the Corvette with independent rear suspension. Depending upon your viewpoint, the SC was either a misunderstood muscle car or an underappreciated American GT—think “big Mustang meets BMW 635i.”

The MN12 was a few inches shorter than the Fox-based Thunderbird, but its 113-inch wheelbase was a whopping nine inches longer, making for a roomy rear seat. It was wider, the cowl was lower, and the windshield was dramatically raked back. This T-Bird was a looker, especially in SC guise with its added aero styling and monochromatic appearance.

All of this, 30 years ago

The SC was also a techno wonder. Its 3.8-liter V-6, an offshoot of Ford’s Windsor small-block V-8, used a Roots-type Eaton supercharger, intercooler and computer-controlled distributorless ignition. With 12-psi maximum boost, output was 210 hp at 4000 rpm and 315 lb-ft of torque at 2600 rpm. (Numerous upgrades boosted output to 230 hp and 330 lb.-ft. in the ’94–95 model) The standard five-speed manual transmission came from Mazda; a Ford four-speed automatic overdrive was optional.

A stock SC could do 0–60 in 7.5 seconds and the quarter-mile in the mid-15s at about 90 mph, impressive for a two-ton car in the mid 1990s. Top speed was about 140 mph. Road & Track wrote, “… the 3.8 puts power to the rear wheels with the smoothness of a monster electric motor.”

The SC was a handler, too, its 0.85 lateral g in league with the smaller, lighter IROC Camaro, but with a far more supple ride. After a 1995 test, Motor Trend wrote, “This is a driver’s car for those serious about their road sport.”

The base T-Bird was not nearly as interesting, saddled with a 140-horse V-6. A 200-hp 5.0-liter V-8 option arrived for 1991, replaced in ’94 by Ford’s 4.6-liter OHC V-8.

Ford threw everything it had at the SC, which started at $20,000 in 1989 (that’s about $41k today). Standard equipment included electronically-controlled speed-sensitive power steering, four-wheel disc ABS brakes, Traction-Lok differential and 16 x 7-inch alloy wheels with 225/60VR16 Goodyear Eagle tires. Later models received low-speed Traction Assist to control rear wheel slippage.

The standard Adjustable Ride Control system used electronically controlled Tokico gas-pressure shocks, with “Auto” and “Firm” modes. The system’s computer monitored vehicle speed, brake-line pressure, steering angle and ECU acceleration signals to switch between normal and firm shock valve settings.

The high-torque SC could easily shrug off the 4,000-pound curb weight, but its small brakes—10.8-inches in front and 10 inches in back—were a drawback. Kreisz replaced his 1992 SC’s brakes with a ’99 Mustang Cobra’s larger rotors, which are not a direct bolt-on.

A peek at the future

If you’re wondering what it might be like to maintain one of today’s highly computerized cars 20 years from now, the Thunderbird SC offers clues. It probably won’t be easy.

“When running right, they’re amazing cars, quiet and smooth to drive,” says Ken Tidwell, who owns an SC 35th Anniversary model. “But the SC was over-engineered in some cases. That can make repairs challenging.”

Tidwell’s past experience as an ASE-certified mechanic has been helpful in addressing the SC’s trouble spots, and he has written an online Ford Thunderbird Super Coupe Buyer’s Guide. Not surprisingly, the SC’s electronics, now decades old, are among those trouble spots.

“The SC was advanced for its time, with lots of sensors,” Tidwell says. “There are distinct processes for troubleshooting. For example, misfires can easily be misdiagnosed. Unless you’re diligent going through diagnostics, you’ll chase it for a long time.”

Like Kreisz, Tidwell recommends joining the Super Coupe Club of America (SCCoA) and its active member forums for information and technical support. He also recommends getting a copy of the factory service manual and the Electrical and Vacuum Troubleshooting Manual. Even routine maintenance can cause headaches—and bruised hands.

“It’s a very crowded engine compartment,” he says. “Changing plugs is very difficult, but they last a long time if the engine is running properly.”

Some key parts are no longer available, including the crank sensor for early models, Tokico electronic shocks, and the ABS accumulator. The SCCoA offers advice on including installing conventional shocks.

SuperCoupe Performance in Milford, Ohio, is one source of parts. Tidwell had built a stash of spares pulled from scrapyard SCs, but he says eBay sellers are now usually getting to them first. Kreisz mines parts from a pair of Cougar XR7s.

In design, performance, handling, technology, and amenities, the Thunderbird SC was a unique muscle-GT with no direct American or imported peer. Three decades later, enjoying one can require investing more money than the car is currently worth. But if you ask owners like Kreisz and Tidwell, it all pays off when you drive it.