1970 Plymouth Cuda Convertible 440 4-Speed: Exploring the 440 Six Barrel Engine

The 1970 Plymouth Cuda Convertible 440 4-Speed is a legendary muscle car that has captured the hearts of car enthusiasts for decades. In this Muscle Car of the Week Video Episode #186, we delve into the details of this remarkable vehicle. From its iconic design to its powerful engine, the 1970 Plymouth Cuda Convertible is a true testament to American automotive craftsmanship.

The Plymouth Barracuda Lineup

The 1970 Plymouth Barracuda lineup consisted of three distinct models: the base model Barracuda, the Gran Coupe, and the sporty CUDA version. The focus of this episode is on the CUDA convertible, which showcases the epitome of style and performance.

One of the standout features of the 1970 Plymouth Cuda Convertible is its shaker hood scoop. Officially known as the IQ ec AG (Incredible Quivering Exposed Cold Air Grabber), this technical marvel is fixed directly to the 440 cubic-inch V8 engine. When you accelerate, the shaker hood scoop shakes and quakes, adding an element of excitement and power to the driving experience.

The Powertrain Options

The 1970 Plymouth Cuda Convertible 440 4-Speed is often overshadowed by the renowned 426 Hemi engine when it comes to discussions about muscle cars. However, the 440 six barrel engine in this Cuda Convertible deserves its own recognition. With outstanding real-world performance and drivability, the 440 engine proves its worth. Equipped with three Holley carburetors, it generates an impressive 390 horsepower at 4700 rpm and a staggering 490 foot-pounds of torque at 3200 rpm. These figures, combined with its high compression ratio of 10.5:1, establish the 440 engine as a true force to be reckoned with on the streets.

The 440 engine’s performance is not merely confined to paper. It delivers exhilarating acceleration and power in real-world driving scenarios. Whether you’re cruising down the highway or challenging other vehicles at stoplights, the 440 engine ensures an exciting and enjoyable experience. Its robust design and well-tuned components enable it to deliver exceptional performance consistently. The trio of Holley carburetors optimizes fuel delivery, ensuring a steady and reliable power output across different driving conditions.

When it comes to the sound and feel of the 440 engine, enthusiasts are not disappointed. The engine’s distinctive roar and the surge of torque when the accelerator is pressed make every drive a thrilling event. The 440 engine exemplifies the essence of American muscle cars, combining raw power with impressive drivability. Whether you’re a collector, an enthusiast, or simply someone who appreciates the art of automotive engineering, the 440 six barrel engine in the 1970 Plymouth Cuda Convertible is sure to leave a lasting impression.

Enhanced Suspension and Handling

The suspension system of the 1970 Cuda Convertible received meticulous attention from the engineers at Plymouth. Notably, the front torsion and sway bars were reinforced, utilizing components borrowed from larger midsize cars. This upgrade enhanced the car’s handling capabilities and stability, allowing for improved maneuverability and control on the road.

However, it was the rear suspension of the Cuda Convertible that boasted a particularly unique setup. On the passenger side, there were five full leaf springs and two half leaf springs, while the driver side featured a full six leaves. This arrangement played a vital role in ensuring that the car could effectively plant its tires evenly on the ground. It helped maintain stability during high launches and provided a level platform for optimal performance.

By carefully fine-tuning the suspension system, Plymouth engineers ensured that the 1970 Cuda Convertible delivered exceptional handling characteristics. The combination of reinforced front torsion and sway bars, along with the innovative leaf spring setup in the rear, contributed to a well-balanced and stable driving experience. Whether taking sharp corners or accelerating from a standstill, the Cuda Convertible’s suspension system provided the driver with confidence and control, making it a truly remarkable muscle car of its time.

The Convertible Advantage and Disadvantage

The 1970 Plymouth Cuda Convertible’s open-top design provides an exhilarating driving experience. However, without the roof structure for support, the convertible model faces a slight disadvantage in terms of rigidity. Nonetheless, the convertible still offers superb performance. It features a nine and three-quarter inch Dana 60 rear axle with a 3.54:1 gear ratio and a limited-slip differential, providing excellent acceleration and cruising capabilities.

The 1970 Cuda Convertible with the 440 six barrel engine is a rare gem in the automotive world. Only 12 of these convertibles were built with an automatic transmission, and a mere 17 were equipped with the heavy-duty four-speed manual gearbox. While not as scarce as the Hemi-powered models, the limited production numbers make the 440 six barrel Cuda Convertible highly sought after by collectors and enthusiasts alike.

Stunning Design and Interior

The 1970 Plymouth Cuda Convertible boasts an eye-catching Alpine White exterior. Its classic and sleek appearance turns heads wherever it goes. The warm tan vinyl interior provides a beautiful contrast to the exterior color. With a manually operated convertible top, the Cuda allows you to embrace the open road and enjoy the wind in your hair.

Inside the Cuda, you’ll find a range of notable features. The dashboard is adorned with a variety of gauges, including a 150-mile-an-hour speedometer and a large 8,000 RPM tachometer. An AM radio completes the vintage feel of the interior. The classic pistol grip shifter controls the four-speed transmission, adding to the overall driving experience. Interestingly, the absence of a console, along with the manual top and crank windows, indicates that the original buyers prioritized performance and power over luxury.


The 1970 Plymouth Cuda Convertible 440 4-Speed is a rare and impressive muscle car that embodies the spirit of American automotive ingenuity. Its unique design, powerful engine, and limited production numbers make it a highly coveted vehicle among collectors and enthusiasts. The Cuda Convertible is a true icon of its time and continues to inspire generations of car lovers to this day.

Leave a Reply

Your email address will not be published. Required fields are marked *