In the annals of Mopar history, there are a number of models we all know as rare in terms of their production numbers. 1970 and 1971 Hemi Cuda convertibles, 1970 Hemi Superbirds, and the 1970 Coronet Hemi Convertible all immediately spring to mind.

There are a number of lesser known Pentastar rarities than these iconic monsters though, and indeed we had a look at one in the very first iteration of this recurring column in the form of the 1970 Chrysler 300 Hurst. In deference to the inescapable fact that I’m a raving Mopar nut, I thought this month we’d again have a look at a rare Chrysler product. So without further ado, I give you the 1967 Plymouth Belvedere II R023!

The mighty 1967 Plymouth Belvedere II R023. (Photo courtesy of Mecum Auctions.)

In order to fully elucidate the details of the ’67 R023, we must first go back in time and trace the lineage of the Plymouth Belvedere.

Introduced as the Plymouth Cranbrook Belvedere in 1951, the somewhat bulbous, pillarless coupe was Chrysler’s answer to the highly successful Ford Victoria and Chevy Bel Air. It was considered to be the top-end, full-sized model in the Plymouth line, and as such was outfitted with a host of luxury features and available options.

The 1951 Plymouth Cranbrook Belvedere pillarless coupe, with its rather porcine body lines. (Photo credit unknown.)

The Belvedere became a popular model from the outset, and spawned the Fury as a high-performance variant. Several redesigns were unleashed upon the car-buying public throughout the ’50s and ’60s that saw the car become increasingly svelte and streamlined, mirroring the general styling trends of the era.

In 1966, Plymouth made the bold decision to re-introduce the Belvedere as a mid-sized model, and further broke with history by dividing the lineup into several distinctly different trims. The Belvedere I, Belvedere II, and Satellite were unleashed as 1967 models, along with a high-performance model known as the GTX.

An original print ad for the 1967 Plymouth GTX. (Photo courtesy of Fiat-Chrysler Automobiles.)

Available as a two-door hardtop or convertible, the GTX was aggressively promoted as The Gentleman’s Muscle Car and was equipped for business with the 375 horsepower Super Commando 440 cubic inch V8 engine and the TorqueFlite 3-speed automatic transmission. Super-duty suspension which included 6-leaf rear springs, thick anti-sway bars, upgraded ball joints and heavy-duty shocks and torsion bars were added to aid in mitigating the extra power.

So as to firmly delineate the GTX from its less-potent stablemates, the car received unique, muscular styling cues including a bespoke grille and tail-panel treatment, non-functional hood scoops, chrome gas cap, bucket seats, and an energy-absorbing steering column. Performance add-ons such as an A833 4-speed manual transmission and front disc brakes with rear drums gave buyers the ability to even further boost the performance.

The heart of the Beast: The 426 ci Hemi V-8 “Elephant Motor.” (Photo courtesy of Barrett-Jackson.)

But it was the 426 Hemi option that really wet the whistles of stoplight warriors across the country. Adding nearly $550 to the car’s price, nearly a fifth of the base price of a GTX, the Hemi nonetheless boosted output by a factory stated (and highly underrated) 50 horsepower. This offered a Hemi-equipped GTX a 13.5-second quarter-mile at 106 mph, nearly two full seconds faster than a 440 car.

Owing to the Hemi’s cost and the possibility for enthusiasts to tune the 440 to approximate its performance, Hemi GTX’s were a rare bird indeed. Not quite as rare though as a little-known performance package offered for the Belvedere II cars.

A great example of mid-’60s Mopar muscle styling. (Photo courtesy of Hagerty.)

Known internally as the R023 option-package, it was colloquially referred to as the Lightweight or Super-Stock option by streeters in-the-know. It was unusual for the fact it didn’t so much add equipment to the car, but rather took a host of things away in an effort to shed as much weight as possible.

With the R023 box checked on the order form, buyers of Belvedere IIs did away with the heater, radio speakers, all body insulation, interior carpets, and hubcaps.

The only external clues to the R023 were the hood scoop and steel wheels. (Photo courtesy of Mecum Auctions.)

Added would be a large, functional hood scoop giving a ram-air effect to a 426 Hemi and its dual Carter 4-barrel carburetors, heavy-duty engine internals, a special intake manifold that had much of the plenum area separators removed, a dual-point distributor, and a transistorized ignition with high performance ignition wires. When equipped with the A833 transmission, Chrysler mandated the Dana 60 SureGrip differential with track-friendly 4.88:1 gears.

Externally, nothing (save for the aforementioned steel wheels and hood scoop) gave a clue as to what the R023 was, which appealed to fans of sleeper brutes. Indeed, the crisp, boxy body lines of the Lightweight were unchanged from the all-steel ones from run-of-the-mill Belvederes and GTXs. All RO23s were delivered wearing white paint, which prompted many buyers to paint them in a more appealing shade.

The interior of the R023. Note the bench seat and the lack of heater and radio controls. (Photo courtesy of Barrett-Jackson Auctions.)

Inside, the R023’s interior was identical to any Belvedere II, with the exception of the missing heater and radio controls.

Because of the relative lack of promotion of the package and the cost it added to an already expensive Hemi-equipped car, only 55 examples of the R023 came off the assembly line. They were all built on the same day, February 12, 1967. Of the 55, only 17 were equipped with the A833 4-speed.

Though no exact performance figures exist for the R023, based on the numbers for a standard Hemi GTX, a mid-12 second quarter-mile can be extrapolated. Quite a runner for today, let alone 1967!

The Sox & Martin GTX R023 dragster. (Photo courtesy of Performance Years Enterprises.)

It is unknown how many R023 cars have escaped the ravages of time and use, but it is known that examples have sold in excess of $200,000. Quite a sum for a car which left the factory for around $5000, but perfectly justifiable for such a potent Rare Ride.

Until next time!