In this edition of Muscle Car Milestones, we’ll take an in-depth look at the 1970 Plymouth Road Runner Superbird. Produced for only one year, this winged warrior has so much history and aura attached to it. A car that is so radical and different, it immediately captures your attention and leaves a lasting impression. A car that stands out like no other from a time when going to the extreme was the norm.
Plymouth’s Superbird – Love it not for itself, but for what it stands for”. A.B. Shuman, Motor Trend, January 1970
Now that the Superbird was ready for the track, it had to be made available for the average Joe to purchase. NASCAR homologation rules dictate that for a vehicle to be raced, a certain number of production cars have to be made available to the general public. In 1970, the rule was changed to a formula based on the number of a brand’s dealers. In the case of the Superbird, the number that had to be built to satisfy those requirements was close to 2,000.
Plymouth didn’t create a car as radical as the Superbird and not give it what it needed to take flight. The standard power plant was the GTX 440 pumping out 375 horsepower and 480 foot pounds of torque. Next up was the optional 440 6-barrel cranking out 390 horsepower and 490 foot pounds of torque. And what Plymouth muscle car would be complete without a Hemi? For drivers wanting the real deal, Plymouth offered a 426 cubic-inch Hemi spewing 425 horsepower and a whopping 490 foot pounds of torque. As usual, production of the Hemi-equipped version is low due to the engine’s hefty price tag. Production numbers were 1,084 for the 440 4-barrel, and 716 for the 440 6-barrel, and only 135 for the 426 Hemi.
The standard transmission offered on the Superbird was the TorqueFlite 727 3-speed automatic. The Performance Axle Package, which included a 3.55 rear axle and Sure Grip differential, was also included with the TorqueFlite. Buyers wanting to manually shift could opt for the available Type A-833 4-speed. When the manual was checked off on the option sheet, the A33 Track Pak was also included. This comprised of a 3.54:1 rear end with a Dana Sure Grip axle.
Asking if the Superbird is fast would be like asking the road runner if he could outrun the coyote. Car and Driver tested the winged warrior and came up with some pretty impressive stats. From 0-60, the 426 Hemi Superbird clocked in at 4.8 seconds and sprinted the quarter mile at 13.5 seconds running 105 mph. Compared to the base 440 engine, the Hemi could distance the quarter .76 seconds quicker.
What an experience it is to see a Superbird for the first time. It’s one of the most visually stunning muscle cars ever created. To say it’s unique would be an understatement. Simply put, it grabs your attention and refuses to let go. Customers could choose from several outlandish paint choices. Plymouth concocted a canvas of vivid colors like Alpine White, Vitamin C Orange, Lemon Twist, Lime Light, Blue Fire Metallic, Tor-Red, and Corporation Blue for this stunner. A visual walk around the car reveals so many features that make this car so remarkable. One of the first things you notice is the aerodynamic nose cone, pop-up headlamps, and spoiler on the front of the car. The spoiler does more than just look good. It eliminates front end lift and lowers drag by limiting airflow under the car. Fender vents and racing-type hood pins are giveaways to the car’s NASCAR roots. The piece that really catches your eye is the giant 24-inch stabilizer wing with Road Runner graphics on the rear of the car. It’s another piece of the puzzle in the Superbird’s aerodynamic design. The nose extension, front spoiler, and rear convex window help reduce drag and the rear stabilizer wing helps increase high speed stability. Many ask why Plymouth would choose to place a vinyl roof on such a graceful car. Truth is, it was to hide the body work needed for creating the aerodynamic rear window.
Inside, the Superbird was all business. A black or white bench seat was standard but customers could dig a little deeper into their wallet and spring for bucket seats. Power steering was standard along with the “beep-beep” Road Runner horn. A 150 mph speedometer, along with temperature and fuel gauges, was also included. Cruising during the summer in the Superbird will be warm since air conditioning isn’t an available feature. Other items left off the option list include rear seat speaker, rear window defogger, and headlamp delay. Plymouth definitely built this car for speed so creature comforts were somewhat lacking.
Plymouth equipped the Superbird with plenty of performance features. The car came with F-70 x 14-inch wide-profile tires as standard equipment. Customers could also choose optional F-60 x 15-inch extra-wide tires. A complete heavy-duty suspension was also standard. Braking power came courtesy of 11.75-inch disc brakes with 10-inch rear drums.
One thing is for sure. If you plan on buying a Superbird, expect to pay a hefty price. In November 2013, a Hemi equipped model with a four-speed sold for $363,000. If that price is too much for your budget, 440-equipped models can be bought for about half as much.
Here’s a couple things about the Superbird you may not know. The EPA used a Superbird to test jet airplane emissions. The Superbird, along with its smog testing equipment, would reach speeds of around 100 mph in order to follow the plane down the runway as it took off to collect emission samples. Also, the Maryland Department of Motor Vehicles banned the sale of the Superbird in that state. Maryland did not consider the front nose cone to be an actual bumper so it declared the car was in violation of the state’s safety laws.
1970 would be the only year the Superbird would be produced. Since NASCAR imposed new engine and weight restrictions on aero cars, Plymouth deemed the car would not be competitive. This car also comes from a time when manufacturers were in competition with one another to create some serious muscle cars. The Superbird is definitely one of the most radical from that time.
Body & Frame
Type: unibody body and frame
Layout: front longitudal
Powerplant: 426 Hemi V8
Displacement: 426 cubic-inches
Horsepower (net): 425 bhp @ 5,000 rpm
Torque (net): 490 ft lbs @ 4,000 rpm
Carburetion: two 4-barrel
Valvetrain: pushrod OHV, 2 valves per cylinder
Bore x stroke: 4.25 x 3.75
Compression ratio: 10.25:1
Fuel system: single 4-barrel carburetor
Exhaust: 2.5-inch diameter pipes into high flow mufflers
Type: TorqueFlite 727 3-speed automatic (including Performance Axle Package), Type A-833 4-speed (including Track Pak)
Type: semi-floating Hypoid “Sure Grip”
Final drive ratio: 3.55 (automatic), 3.54:1
Type: recirculating ball with power assist
Front: 10.97 x 6.98 vented disc, floating caliper
Rear: 10 x 2.5 drum
Front: independent, lateral, non-parallel control arms with ball joints and torsion bars
Rear: extra heavy duty, semi-elliptical springs
Wheels & Tires
Wheels: 14 x 7-inch wide (standard)
Tires (new): F-70 x 14-inch wide profile (standard), F-60 x 15-inch extra-wide (optional)
Wheelbase: 115.8 inches
Length/Width/Height: 221/76.4/61.4 inches
Curb weight: 3,785 pounds
Front track: 59.7 inches
Rear track: 58.7 inches
Fuel tank capacity: 19 gallons
0–60 mph: 4.8 seconds
Quarter mile: 13.5 seconds
1970 Plymouth Superbird Photo Credits: