How did the Road Runner do with the bean counters in Highland Park? For 1969, very well. With total-series sales of 88,415, which included 48,549 hardtops, 2,123 convertibles, and 33,743 coupes, it was the best-selling midsize Plymouth line of all. The Road Runner two-door hardtop was Plymouth’s best-selling two-door car of any kind.
NEW STYLING, NEW COLORS, NEW “SYSTEM”
The third-year Plymouth Road Runner debuted in 1970 with front-end styling that foreshadowed a major restyling of Chrysler’s B-Body platform in 1971. Steel Rallye road wheels were a popular option; they are now being reproduced. (Photo Courtesy David Newhardt)
The third-year Plymouth Road Runner still retained its original character as a purpose-built stripped-down muscle car that provided exceptional performance and rugged reliability. The 1970 model was an evolution of the two previous models, so it was not substantially changed, but it did receive some important updates. Although a multitude of small improvements were made, the most noted and recognizable changes were to its interior and exterior styling.
It arrived in the nation’s Chrysler-Plymouth dealers in September 1969, and Plymouth’s Styling studios developed a new look inside and out to distinguish it from the previous model years. The third-year Bird wore new front fenders, rear-quarter panels, grille, taillights, and bumpers, as did its GTX/Satellite/Sport Satellite/Belvedere stablemates. They also shared a new, squared-off look front and rear, with a “center scoop” motif to the grille and rear body above the bumper. Carried over from 1969 were the coupe/hardtop roof, convertible top, and all the windows.
The Road Runner for 1970 combined that updated styling, which included simulated scoops on the rear-quarter panels and new optional Rallye road wheels on the outside, plus a new dash, Pistol Grip 4-speed shifter and high-back bucket seats, with a proven high-performance powertrain and chassis. It was all wrapped up in the strongest and lightest-weight midsize passenger car platform made in 1970.
As a member of the Chrysler B-Body family, the Road Runner used Chrysler’s Unibody unit-body construction method, which “surrounds you in strength” thanks to stout structural members welded into and underneath the body.
Since 1960, using state-of-the-art computer technology, Chrysler’s body engineers added structural strength to new body designs where needed, resulting in a unit-body assembly that was more resistant to flexing and bending than a conventional (body on frame) body was without the added weight of a full frame underneath the car. The resulting squeaks and rattles come from body bolts and connectors coming loose as the car ages.
Unibody, therefore, was the ideal method for constructing high-performance car bodies, such as the Road Runner’s. For the severe-service applications such as the 426 Hemi, additional structural reinforcements were developed and welded in the appropriate bodies-in-white before they were made ready for primer and paint. After all, Chrysler engineered its high-volume B-Body platform to carry its full range of engines, from the standard 225 Slant Six and 318 LA series small-block V-8 to the B and RB big-blocks (the 383s and 440s) and the 426 Hemi.
The extra structural strength came from large structural subframes and crossmembers at the front and rear. One large crossmember is installed at the rear, just ahead of the rear axle and connects the two frame rails, essentially “boxing” the rails. On hardtop and coupe models, thick roof bows deliver added strength and rigidity to the roof panel. Up front, cowl panels, radiator support, and fender wells are tied together for improved strength. In addition, 426 Hemi-equipped cars received their own unique engine crossmember (the K-member), specially engineered for the Hemi’s weight and to prevent its massive torque output from twisting the car’s Unibody into a pretzel at full throttle.
The Unibody had been proven in thousands of Plymouths, Dodges, Chryslers, and 1967 and later Imperials that preceded the third-year Road Runner into production.
A totally new B-Body body design was in the works for 1971; 1970 marked the final year of the generation of midsize Plymouths and Dodges that had debuted for 1966.
Beyond the styling and comfort improvements, the Air Grabber cold-air induction featured a revised design and operation for the 1970 model year. The Road Runner’s steel hood was changed from the parallel-twin-scoop design that was used in 1968 and 1969 to one with a large center bulge that accommodated the vacuum-operated Air Grabber scoop and the big carburetors that resided on top of the engine. A dash-mounted switch activated a servo, which raised and lowered the scoop. Once it was deployed, the shark teeth graphics (that resembled the nose art on the legendary Flying Tiger fighter planes of World War II) were clearly visible on each side, adding to the car’s street credibility and increasing its intimidation factor over other car brands’ attempts at cold-air induction.
The standard Road Runner engine was a high-output version of Chrysler’s venerable 383-ci B-engine big-block V-8. Its cylinder heads, camshaft, and other components were borrowed from the 440 Magnum. Here, Coyote Duster artwork graces the air cleaner that was included with the optional Air Grabber hood (Code N96).
The coupe was still the most affordable Road Runner in 1970. Its sticker started at just under $3,100 and included potent high-performance hardware such as its standard 383 and heavy-duty suspension. The Dust Trail stripe along the side was a $15.55 option. Bright trim on the B-pillar denotes this car as having the Code A87 Decor Package, which added Satellite-level bright trim inside and out for an extra $81.50.
Although the Road Runner’s available engine lineup remained the same for 1970, a high-performance floor-shifted 3-speed manual gearbox became the standard transmission; the A-833 4-speed and TorqueFlite automatic were offered as options. The A-833 was one of strongest as well as heaviest 4-speed manual transmissions built during the muscle car era. Through the 1960s, the A-833 was continually developed and improved upon, and by 1970 it was offered in two versions. One was known as the 23-spline version so named for the number of splines on its input shaft that was used on all but the highest-output V-8s including the 426 Hemi and 440 Six Barrel. For those applications, the so-called “Hemi 4speed” (also known as the 18-spline version) was specified for 426 Hemi duty, and installed on the assembly line. That gearbox’s strength was evident in its input shaft because the splines (and shaft itself) were thicker than those used with the 23-spline unit. Regardless of which 4-speed your Road Runner was built with, a Hurst 4-speed shifter was standard equipment from the factory, and did not need to be retrofitted immediately after the car was purchased.
Once again for 1970, the A-727 version of Chrysler’s rugged TorqueFlite automatic was optional on all Road Runner engines, even the 426 Hemi. In service since 1964, and noted for its smooth shifting and reliability even under severe-service conditions, this heavy-duty automatic did not require the frequent band adjustment or other service procedures that rival automatics from Ford or General Motors required.
Similar to 1969 models, the base engine for 1970 was the special Road Runner 383, and there were just two engines on the option list: the 440 Six Barrel and the 426 Hemi. (The four-barrel-equipped 440 Magnum was GTX-only for 1970; it was not offered on the Road Runner until 1971.)
The base Road Runner 383 engine was no