Sublime Green 1973 Plymouth Road Runner Is No Lemon Thanks to Supercharged HEMI V8

Which year is another story, though, as the jury is still out on that. Some say the muscle car was ousted in 1971, a few years after President Richard Nixon signed the Clean Air Act. Others claim that the era did not end until 1974 when Pontiac discontinued the GTO. The latter, however, was just a 200-horsepower option to the Ventura.

As for me, the muscle car met its doom at the end of the 1971 model year. Sure, Ford still offered a 275-horsepower (net) Mustang in 1972, but General Motors and Chrysler discontinued their high-compression big-block engines after 1971. More importantly, Mopar eliminated both the 426-cubic-inch (7.0-liter) HEMI and the 440-cubic-inch (7.2-liter) Six Pack from the options list.

Granted, the Malaise Era didn't take over until 1974, but 1972 was the first model year without fully-fledged muscle cars, as far as I'm concerned. Does this mean the muscle car nameplates that survived through the mid-1970s didn't spawn cool rigs after 1971? Hell no! The Plymouth Road Runner, for instance, remained a solid option design- and even performance-wise.

Indeed, the 1970 version remains my favorite in terms of looks, but the rounded "fuselage" styling that Plymouth introduced for the 1971 model year is quite appealing too. The squared-up design of the 1973-1974 variant is not too shabby either. I prefer it over the Ford Torino and Chevrolet Chevelle (yuck!) of the era.

These Road Runners were exactly underpowered, either. In 1971, the range-topping, four-barrel 440 still generated a decent 280 horsepower (net). The same mill came with 275 horses on tap for the 1974 model year. Still concerned about not having enough power in a post-1971 Road Runner? Well, this 1973 version proves that oomph isn't something you have to worry about if you're not hooked on keeping your Mopar factory stock.

It's the 21st century, baby, and the market is flooded with aftermarket options that will turn any mid-1970s lemon into a proper muscle car. Yup, this 1973 Road Runner is one of those highly modified restomods that packs a nasty V8 under the hood.

The result of an extensive rotisserie rebuild, this Mopar flaunts a Sublime Green coating that reminds of the golden muscle car era. If you're unfamiliar with High Impact colors, Sublime was first offered on Chrysler vehicles in 1970. It was called Sublime on Dodges, but Plymouth named it Lime Light. Since this Road Runner is coated in a modern, two-stage iteration of the hue, Sublime Green is an appropriate name despite the "Plymouth" badge.

The exterior is fully customized beyond the paint, featuring narrowed and tucked bumpers, a laser-cut grille, shaved handles, LED lights, and Boyd Coddington wheels. Most of the interior is still reminiscent of the stock 1973 Road Runner, but it's packed with modern features and rounded off by custom upholstery and a 12-point roll cage.

Then there's the engine, a blueprinted and supercharged V8 that sounds like all hell will break loose when the pedal hits the metal. Built by Total Engine of Bloomington, Minnesota, the 446-cubic-inch (7.3-liter) lump is based on a 426 Mopar block and includes more performance parts than I can list here.

But I'm going to mention the dual Holley HP Series four-barrel carburetors and the Blower Shop 8-71 supercharger that pop through the hood. How much oomph does this monster of an engine send to the rear wheels? Unfortunately, our host doesn't provide us with that piece of information, but this blown HEMI must be good for at least 800 horsepower—more than fitting for such a show stopper.

Take a tour of this fabulous "pro street" Mopar in the video below. And if you're in the market for a green mean machine, this beefed-up Road Runner is available for $124,900. That's less than a Porsche 911 Carrera S!