In 1965, the muscle car war was just starting to brew. Ford had come out with its now famed Mustang late in 1964, spawning ideas of more muscular models from the likes of Chevrolet, Plymouth, and Buick to follow. As one of the major players in the developing muscle car era, Dodge too was knocking heads to come up with the latest and greatest offerings to bring consumers to their side rather than push them towards their competitors. But while the Charger was developed new for the muscle car scene, it was actually a model that had existed in Dodge’s lineup before that began demanding attention in the mid-sixties model year. Of course, we’re talking about the Coronet 426 HEMI.

While the 1966 and 1967 Coronet HEMIs are rare enough, this ’66 four-door is one of just five believed to have been produced in the entire run of the Coronet HEMI legacy. Because of its rarity, this particular car sold for $660,000 at the 2007 Barrett-Jackson Scottsdale Auction. Image: Barrett-Jackson

A Long Running History

Classic 1955 Dodge Coronet. Image: ClassyCars.org

Introduced originally in 1949 as one of Dodge’s first postwar models, the Coronet held the highest trim level in the full-sized passenger vehicle category until 1955. In it’s third generation, the Coronet name dropped to the lowest trim level and by 1960, the model was no longer in existence. But that didn’t stop Dodge from bringing back the steadfast Coronet name starting in 1965, only this time, the namesake was attached to a mid-sized entry in the market. Basically, the cars offered under the Coronet name were refreshed Dodge Polaras from 1963 and 1964. Despite this fact, the Coronet was the highest selling model under the Dodge brand in 1965.

Despite its popularity, the fifth-generation Coronet was missing something. Chrysler had officially come out with its 426 HEMI engine nicknamed the “Elephant Engine” a year prior with buzz around the NASCAR circuit dubbing it the latest and greatest. Unfortunately, the Chrysler HEMI was not allowed to be used in NASCAR racing in 1965 due to its lack of availability in actual production models.

So that year, Chrysler introduced the “Street HEMI”, a de-tuned 426ci race HEMI that would place Chrysler atop its competition both on the track and on the street.

Image: Auctions America

In mid 1965, you could order any Coronet model with the 426ci Street HEMI engine from the factory for the 1966 model year, although due to its price and power, only a small number of vehicles were equipped with this option. In fact, only 732 Coronets equipped with the potent Chrysler powerplant were built in 1966, according to Hagerty.

The HEMI engine was available for 1965, although it was not warranted by the company or officially offered to the public.

By 1967, Chrylser mandated that HEMIs could only be put in their badged muscle car models; i.e. the Charger, new-for-1967 Coronet R/T and the Plymouth Belvedere GTX. Still, a few lower trim level Coronets squeaked through the ranks with 426ci beasts nestled under their hoods. According to Hagerty, a mere 340 HEMI Coronets were ordered for the 1967 model year, although other sources suggest even fewer (238) were manufactured.

Underrated at 425hp, the Chrysler Gen 2 HEMI that made its way into the mid-sixties Dodge Coronet was race built, but street proven. However, that didn’t mean that the engine wasn’t still a bit rough around the edges. Image: ConceptCarz

The Potent 426 Street HEMI

When the 426 race HEMI was introduced in 1964, it was the largest engine in racing at the time, thanks to its 10.72-inch deck height and 4.80-inch bore spacing. In street form, the HEMI’s massive size didn’t change but some internal components did.

To make the Street HEMI easier to handle on the street, the new engine received a toned down camshaft and related components, different pistons, which lowered the compression ratio from 12.5:1 to 10.25:1, and an aluminum dual quad intake manifold, which rendered the engine’s two Carter four-barrel carburetors one behind the other rather than side by side like on the race-built HEMI.

Image: Auctions America

At the time, Chrysler rated the Street HEMI-equipped Dodge Coronet at 425hp, although like many classic muscle cars, this was believed to be highly underrated with figures closer to 460hp believed to be more accurate. The torque rating for the engine was 490 ft-lbs. This gave the Coronet a zero to 60mph time of 6.1 seconds and a quarter mile time of 14.5 seconds.

Backing the potent HEMI engine was a standard three-speed TorqueFlite automatic transmission or optional three and four-speed manual gearboxes.

A heavy-duty suspension system, red-rim tires, standard 11-inch drum brakes, and optional front discs were just a few more things the HEMI-powered Coronets had to offer.

Image: Barrett-Jackson

Styling Ques

For the 1966 model year, the Coronet was revamped just in time for the factory HEMI option, giving the car a shorter but wider body to compliment the similar B-body-based Charger’s new fastback model. The Coronet also received more sculpted sides, bolder body lines, mesh grilles and large square taillights.

Image: My Classic Garage

In 1967, the Coronet received even more Charger-esque design cues, including a new single-piece grille, although the Coronet’s grille featured headlights that were always visible, unlike those on the Charger. The 1967 model year was also the year that Dodge introduced its Coronet R/T, a sportier Coronet with a heavy-duty transmission, simulated rear fender vents and unique faux hood vents.

The R/T model, which stands for Road and Track, was available in a two-door hardtop and a much rarer convertible version. Coronet R/Ts were available with either the standard Magnum 440ci engine or optional 426 HEMI engine. 

Inside the car, you’d find a similarly sporty interior, complete with bucket seats. Adding a tachometer was an additional choice.

While the Charger and Coronet were similar in design and sported similar engine options, the Coronet was marketed in 1967 as more of the muscle car of choice for performance enthusiasts, where as the Charger was marketed more as a performance touring car. Oddly enough, it was the Coronet that was aimed at being a direct competitor to Pontiac’s GTO, even though today the Charger is the more popular muscle car model from the classic Dodge lineup.

The Slow Demise Of A Legend

The Coronet model remained a staple in the Dodge lineup through the 1976 model year, but the 426 HEMI didn’t last that long. Unfortunately, the last time the Coronet saw a 426 HEMI option was in 1970. After that, the 440ci “Magnum” engine took over as the top-of-the-line engine for the Coronet line, slowly decreasing in horsepower until the seventh-generation lineup eliminated it all together. 

Image: Barrett-Jackson

By 1975 when the seventh-generation Coronet made its debut, the model had strayed so far from its muscular form, as many classic muscle cars had by that time, that there was little of the once HEMI-equipped powerhouse to mourn. Two years later, the Coronet name disappeared all together.

While the Coronet’s late fifth generation (1968-1970) overshadowed the 1966 and 1967 models in many ways, thanks to heat of the muscle car era, those muscle-bound late sixties models would have been nothing without the road paved by previous Coronet HEMIs. After all, in the muscle car game, it was that HEMI and the cars it was attached to that set Dodge apart from other muscle car manufacturers of the day and made a name and reputation for the brand that holds up nearly 50 years later.  

With looks this good and a nasty HEMI under the hood, we don’t know why the Dodge Coronet HEMI isn’t on everyone’s muscle car wish list! Image: Old Muscle Cars