• 2017

The Elephant in the Room

Hot Topics    MRC   

No engine in automobile history lights the performance fuse like the HEMI® engine. Mopar® carries on the legacy of the venerable HEMI engine with crate motors of various sizes and horsepower output, blocks, cranks, heads and most anything else needed to recreate the rumble and raw power of this automotive icon.


The hemispherical head design that was the foundation of the HEMI engines got its start in the ’30s and ’40s as a HS963_011DGdevelopment for military equipment applications. The first official Generation I HEMI engine did not appear in a production vehicle until 1951.

The Firepower V8 debuted in high line Chrysler brand vehicles as a 331-cubic-inch powerplant capable of propelling a car down the ¼-mile in roughly 18 seconds and reaching more than 80 mph. Pretty conservative for what was to come. Racers took note of the engine, and it quickly became a winning element of competition. By 1954, Lee Petty won Daytona and a NASCAR Championship with a Firepower V8. Then, the 1955 Chrysler C-300 changed production car history when a 300-hp version was introduced.

By the end of the decade, the Gen I HEMI engine phased out of production with a Chrysler C-300 offering 375 hp.


Automotive history was rocked again when, in 1964, Chrysler Corporation unveiled the Gen II 426 Race HEMI engine and it quickly dominated racing venues across the country. The next-generation HEMI engine featured 426 cubic inches of over 426 horsepower and monstrous torque. Not surprisingly, it was quickly outlawed since there was no street version in showrooms.

HS963_012DGIn 1966, Chrysler Corporation unveiled the 426 Street HEMI engine in 1966 models to the delight of hot rodders and performance enthusiasts everywhere. The Gen II Street HEMI engine would set the standard for performance for the next five years, through the peak of the muscle car era.

Even today, any factory-produced HEMI engine car brings top dollar for its collectability and street swagger. The limited production of the engine makes it a magical piece. Mopar and its line of Gen II components like heads, blocks and valvetrain pieces keep this legend alive.


The smothering emissions standards, gas shortages and market changes put an end to high-horsepower performance cars in the showrooms by the mid ’70s. The 426 HEMI engine was retired by then.

In 2003, Chrysler Corporation introduced the Gen III 5.7L HEMI engine in street form and the legend picked up whereBU015_275EV it had left off. Mopar quickly followed suit with crate motors, internal bits and just about anything needed for performance enthusiasts to build a Gen III HEMI engine of their own.

Today, more “conservative” Mopar Gen III crate engines can be ordered in 5.7L or 6.4L versions generating 485 hp and 475 lb.-ft. of torque.

To make it easier for vintage Dodge and Plymouth muscle car owners to install a Gen III HEMI® engine in pre-1975 vehicles, Mopar® offers HEMI engine kits that include a power distribution center, a powertrain control module (PCM), engine and chassis wiring harnesses, an accelerator pedal, O2 sensors (and more) to accommodate a 5.7L or 6.4L engine. Details can be found at Mopar.com/crateHEMI.

Mopar continues the tradition of horsepower and performance that makes up such a big part of its DNA. While Mopar social networks continue to nourish and grow the legacy and celebrate the history, recently ringing in the 50th anniversary of the 426 HEMI engine and recognizing every April 26th (4/26) as Happy HEMI (engine) Day.

TAGS:   |   |   |   |   |   |   |   |