1971 Plymouth GTX 440+6

Buzz

The 1971 Plymouth GTX 440+6 stood out as one of the rare muscle cars of its time that required no justification. It was daring, it was powerful, and many considered it stunning.

The Plymouth GTX once again served as the upscale counterpart to the more affordable Road Runner. Both models were part of Chrysler's redesigned midsize lineup, which also featured the Dodge Charger. They boasted sleek new "fuselage" styling on a slightly shorter wheelbase. The updated design included a three-inch wider rear track for improved handling, along with a redesigned interior offering better comfort and ergonomics.

While Mopar was the last among Detroit's Big Three to reduce power, not all its V-8 engines avoided detuning. For example, the standard 383-cid four-barrel in the Road Runner saw a 35 bhp drop. However, GTX engines remained largely unaffected. Although compression ratios were slightly reduced, the standard 440 four-barrel and the optional 440+6 with triple-two-barrel lost only five bhp, dropping to 370 and 385 bhp, respectively. The rare 426 Hemi retained its 425 bhp. Four-speed manuals and TorqueFlite automatics, with axle ratios up to 4.10:1, were still offered, along with the Air Grabber hood.

Despite a weight increase of around 170 pounds, the 1971 GTX's quarter-mile times slowed by nearly a full second in some tests. It featured the firmest suspension settings among Mopar intermediates, and while handling was decent, many reviewers felt the harsh ride wasn't justified. Nevertheless, the car still delivered impressive performance, achieving under 14 seconds and over 100 mph in the quarter-mile.

"Overall," Car and Driver noted, "the Plymouth GTX represents progress in a field where others are stepping back. It shows significant improvements in areas like styling and driver comfort, though performance has slightly declined due to increased weight."

Ultimately, the GTX fell victim to the trends that doomed high-performance vehicles, with 1971 marking its final year. The more widely recognized Road Runner name continued until 1975, but by then, it was more a nostalgic reminder of muscle cars than a true contender. At least the GTX bowed out while still packing its powerful engines.

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The 1971 Plymouth GTX 440+6

Specifications

Wheelbase, inches: 115.0

Weight, lbs: 4,000

Number built: 135

Base price: $3,800

Standard Engine

Type: ohv V-8

Displacement, cid: 440

Fuel system: 3 x 2bbl.

Compression ratio: 10.3:1

Horsepower @ rpm: 385 @ 4700