Plymouth finally got the performance angle right for 1970, and they went full force into it. The Barracuda was moved over to the E-body platform, which it shared with the new Dodge Challenger. The Barracuda rode on a two inch shorter wheelbase than the similar Dodge Challenger, even though its overall body dimensions were the same. The performance models were called ’Cudas and featured five different V8s, the 340, 383, 440, 440+6, and the almighty 426 Hemi.
The 440s and the Hemi cars received a special high performance suspension to put all that power to the road. Standard Barracudas came with a flat hood, while ’Cudas came with standard dual non-functional hood scoops. Optional on all ’Cudas (and standard on Hemi’s) was a very functional shaker scoop, so named because it attached directly to the engine, and poked up through a hole in the hood and thus "shaked" whenever the engine did. The Hemi cost $871 and was installed on just 652 hardtops (out of 17,242) and 14 convertibles (out of 550) copies. It sported hydraulic lifters and was easier to tune than in previous years. The 440+6 was a bargin at just $250 and could keep up with the Hemi till about 70 mph. Both engines were tricky to drive: the 440+6 vacuum-actuated front and rear carbs came on with little warning, while the Hemi’s stiff throttle linkage sometimes snapped all eight barrels open at once.
Plymouth also built a special model for 1970: the Plymouth AAR ’Cuda. AAR was taken from Dan Gurney’s All-American Racers, which raced ’Cudas in he Sports Car Club of America Trans-Am racing series. But whereas Ford and Chevrolet built special models (Boss 302 Mustang and Camaro Z28) meant to mimic the race cars, Plymouth built a street rod. Along with the similar Dodge Challenger T/A, the AAR ’Cuda sported a unique 340 cid V8 with 3x2 carbs that pumped out 290 bhp. The exterior was definitely unique with a matte-black lift-off fiberglass hood, through body-side strobe stripes, tri-colored AAR shield, and standard black ducktail spoiler. The AAR ’Cuda also had special shocks and recambered rear springs which raised the rear end 1 3/4 inches over the regular ’Cuda which allowed clearance for exhaust pipes that exited in front of the rear wheelwell (after routing through the standard muffler beneath the trunk). It also permitted the use of larger tires in the rear, one of the first uses of wider rear tires on a production automobile.
The Plymouth Barracuda continued into 1971 with minor styling changes, including a segmented grille with twin headlamps, dummy front fender vents, and segmented tail lamps. A full range of engines were available and the top performance models were once again called ’Cudas. The AAR ’Cuda was no longer available. To deal with increasingly strict emission laws, Plymouth was forced to detune some of their engines, resulting in a drop in the power ratings. Only 115 Hemi ’Cudas were sold and Plymouth decided to retire the Hemi engine before it had to be detuned to meet the new emission standards. Therefore, the Hemi would end its reign as the most feared and possibly most influential engine of the muscle car era.
1972 was a sad year for performance fans as the mighty Hemi and the 383 engines were retired because they couldn’t meet the new emission standards. The remaining engines had to be detuned and were now rated in net horsepower numbers, which on the surface seemed like a huge drop in power. Unfortunately, the top engine choice for the Barracuda was the 340 cid V8 and the convertible was no longer available.
New safety regulations forced the vehicle to have large front and rear bumper guards in 1973 and 1974. The Barracuda hung on through 1974, after which it was discontinued in the midst of the 1973 oil crisis. Production ended ten years (to the day) after it had begun. Although today they are considered one of the most sought-after muscle cars of all time, the third generation was a marketplace failure and never successfully competed with rival offerings from Ford and General Motors. The rarity of specific models and combinations today is primarily the result of low buyer interest and production at the time.