Every Important HEMI Engine Ever Created, Ranked By Power Output

Detroit has built a lot of legendary performance cars with powerful engines, but only one of those powerplants is a legend unto itself: the Chrysler Hemi. From 1951 through the present, the Hemi engine has undergone an evolution of displacements and power outputs, but the one thing that has remained constant is that the fastest cars of their era always had one under the hood. From showing off at a red light to all manner of professional racing, the Hemi has a history of taking pink slips and checkered flags.

So-called because of the hemispherical combustion chamber, the Hemi squeezes more ponies per cubic inch of displacement than any other engine by burning fuel quicker and more efficiently. The Ford 429 Super Cobra Jet V-8 produced 375 horsepower and 420 pound-feet of torque, while at three cubic inches smaller, the 426 Street Hemi cranked 425 horsepower with 490 pound-feet of torque. As amazing as that was in 1965, engineers have been tinkering with the Hemi engine ever since and have managed to pull over 1,000 horsepower out of it.

In order to give you the most up-to-date and accurate information possible, the data used to compile this article was sourced from various manufacturer websites and other authoritative sources, including MotorTrend and Car and Driver.

10 331 HellFire

300 Horsepower

Chrysler initially designed a hemispherical engine for military use in fighter aircraft and armored vehicles. Some of these massive powerplants were V-12s and V-16s capable of generating up to 2,500 horsepower. As awesome as that sounds, there was no practical use for them in a civilian automobile at the time, and a more useful engine was developed as a 235ci Hemi V-6. This never went into production because it was expensive to produce, but did inspire a new generation of Chrysler engines.

331 HellFire Models

• 1951–1955 Chrysler New Yorker
• 1951–1954 Chrysler Imperial and 1955 Imperial[a]
• 1951 Chrysler Saratoga
• 1952 Chrysler Saratoga Club Coupe
• 1952 Chrysler Imperial Parade Phaeton
• 1954 Dodge C Series
• 1955 Chrysler C-300

Released for the 1951 model year, the 331ci FirePower V-8 was the most powerful engine offered by an American automaker. It was a hemispherical engine, but didn’t bear the name Hemi, because marketing at the time thought FirePower sounded cooler. Under the hood of the Chrysler C-300, the engine was fitted with dual Carter WCFB four-barrel carburetors, producing 300 horsepower. With a top speed of 127.6 mph, the 331 Firepower C-300 was dominant in NASCAR and labeled the “world’s fastest stock car.”

9 392 HellFire

375 Horsepower

The hemispherical FirePower engine was used throughout all of Chrysler’s divisions between 1951 and 1959 in 15 different displacements, from 246ci to 354ci. Then, in 1956, they rolled out the 392 HellFire, which was the mutha of all engines at the time. It was offered in two configurations; a 325 horsepower single four-barrel carburetor version and the 375 horsepower dual four-barrel upgrade. The second of these two was exclusively for the Chrysler 300C and 300D models, making them the baddest things on the road and the track.

392 HellFire Models

• 1957–1958 Chrysler New Yorker
• 1957–1958 Imperial Custom, Crown, and LeBaron[a]
• 1957 Chrysler 300C
• 1958 Chrysler 300D

There was an ultra-rare third variant of the 392 called the “Electrojector” which was an early attempt at fuel injection, which bumped the horsepower up to 390. Only 16 of these were made and 15 of them were recalled and fitted with carburetors because the technology wasn’t quite there yet and they were unreliable. The 392 Hellfire was such a killer engine that drag racers and hot rodders used them well into the 1970s to blow doors off.

8 Ball-Stud Hemi

375+ Horsepower

Any list of important Hemi engines would be incomplete without the Ball-Stud Hemi seen in the video above. Though it was just a prototype that never made it into production, it holds a special place between generations and influenced the modern Hemi engine production line. In the late 1960s, Chrysler was looking to replace the 426 Hemi, which was expensive to produce, as well as their other big V-8s which were made from different blocks, with a unified block platform.

Ball-Stud Hemi Facts

• The Engine was affectionately called the “BS Hemi”
• Between 3 and 12 Ball-Stud Hemis were built
• Only one has survived
• The lone BS Hemi was dropped into a 1969 Barracuda
• The BS Hemi ‘Cuda is on display at the National Auto and Truck Museum

The Ball-Stud Hemi, named for its ball-stud-style rocker arms, was built in two sizes: 400ci and 444ci. Though official power data has never been released, it was rumored that the 444 performed better than the 440 but less than the 426 Hemi. That would put its output somewhere between 375 horsepower and 425 horsepower, which ain’t bad. A variety of things from the price of gas to shifting consumer trends conspired to kill the Ball-Stud Hemi, but the idea of a single-block Hemi platform would be revived in the coming decades.

7 5.7-liter Hemi

399 Horsepower

The 426 Street Hemi was retired from production models in 1971, though it would continue for a few more years as a crate engine. After a 32-year absence, the Hemi engine made a glorious comeback in 2003 with a 5.7-liter V-8. Originally used only in Ram trucks, as a replacement for the 5.9-liter Magnum engine, Chrysler saw how awesome it was and soon made it available to other models, most notably the rebooted Dodge Charger and Challenger.

5.7-liter Hemi Models

• 2003–2024 Ram Pickup
• 2004–2009, 2011–2024 Dodge Durango
• 2005–2008 Dodge Magnum R/T
• 2005–2022 Chrysler 300C,
• 2010, 2012–2023 Chrysler 300S V8
• 2005–present Jeep Grand Cherokee
• 2006–2023 Dodge Charger R/T
• 2006–2010 Jeep Commander
• 2007–2009 Chrysler Aspen
• 2009–2023 Dodge Challenger R/T
• 2022–2023 Jeep Wagoneer

Originally rated at 345 horsepower, a 2009 upgrade stretched those ponies out to almost 400. The rebooted Hemi engine proved to be versatile, making 375 horsepower in the 2009 Challenger R/T 6-speed manual and jamming 399 horsepower under the hood of the 2009 Dodge Durango HEV. Though only 347 cubic inches of displacement, the 5.7-liter Hemi achieved higher performance with complex new heads that create more consistent combustion. More importantly, muscle cars finally had a Hemi again.

6 6.1-Liter Hemi

425 Horsepower

The success of the re-introduction of the Hemi engine in 2003 set in motion a horsepower race that began with the 6.1-liter Hemi in 2005. Rated at 425 horsepower, it was the first engine to match the legendary 426 Street Hemi’s output, but its 420-pound feet of torque wasn’t quite as good as the 490 made by its grandfather. Initially equipped in the Chrysler 300C, it soon found its way into all Mopar SRT8 performance trims.

6.1-liter Hemi Models

• 2005–2010 Chrysler 300C SRT-8
• 2006–2008 Dodge Magnum SRT-8
• 2006–2010 Dodge Charger SRT-8
• 2006–2010 Jeep Grand Cherokee SRT-8
• 2008–2010 Dodge Challenger SRT-8

Things get a little confusing on this engine, courtesy of Car and Driver. While they didn’t review the 2010 Challenger, they published a list of specs and features for the 2010 Dodge Challenger SRT Hellcat SRT8 2dr Cpe with the 6.1 Hemi V-8. They also spec’d the 2010 Dodge Charger SRT Hellcat SRT8 4dr Sdn, and like the Challenger, it has the 425 horsepower 6.1-liter Hemi V-8, which is clearly not a Hellcat engine. Maybe it was a special performance package, but no other reference to a 6.1-liter Hemi Hellcat can be found.

5 426 Street Hemi

425 Horsepower

After Chrysler retired the HellFire hemispherical engines in 1958, they began developing a bigger 426ci version for use in racing. The engine was so powerful that it dominated NASCAR and, after complaints from Ford, was banned for the 1965 season because it was not available in production vehicles. To meet the homologation requirements and get back on the oval track, Chrysler started dropping the legendary 426 Street Hemi under the hoods of its already amazing muscle car line-up.

426 Street Hemi Models

• 1966–1970 Dodge Coronet/Plymouth Belvedere
• 1966–1971 Plymouth Satellite
• 1966–1971 Dodge Charger
• 1967–1971 Plymouth GTX
• 1968 Plymouth Barracuda
• 1968–1971 Dodge Super Bee
• 1968–1971 Plymouth Road Runner
• 1969 Dodge Charger R/T
• 1969 Dodge Charger Daytona
• 1970 Plymouth Superbird
• 1970–1971 Plymouth Hemi ‘Cuda
• 1970–1971 Dodge Challenger

Introduced into production vehicles in 1966, the 426 was the first engine to use the Hemi name, and Chrysler went so far as to trademark it. Making 425 horsepower and 490 pound-feet of torque, the 426 Hemi made Dodge and Plymouth muscle cars the fastest on the street during the classic era. As untouchable as Hemi cars were back then, they’ve become high-dollar collectibles now because of their rarity. Only around 9,000-11,000 examples were ever equipped with a 426 Street Hemi between 1966 and 1971, with many survivors now selling in the millions.

4 392 HEMI

485 Horsepower

In 2005, Chrysler built a crate 6.4-liter Hemi that was rated at 525 horsepower and 520 pound-feet of torque. The displacement of this engine was not random because 6.4 liters is equivalent to 392 cubic inches, which is the size of the classic HellFire V-8 that put Mopar performance on the map. Sold as the stylized 392 HEMI, it eventually found its way into production cars, becoming the go-to Mopar engine option.

392 HEMI Model

• 2023 Chrysler 300C
• 2012–2014 Chrysler 300 SRT-8
• 2011–2023 Dodge Challenger SRT-8/SRT 392/Scat Pack
• 2012–2023 Dodge Charger SRT-8/SRT 392/Scat Pack
• 2018–2024 Dodge Durango SRT
• 2012–2021 Jeep Grand Cherokee SRT-8/SRT
• 2022–2023 Jeep Grand Wagoneer
• 2021–present Jeep Wrangler Unlimited Rubicon 392

The 2011 Dodge Challenger SRT8 came equipped with a version of the 392 HEMI that produced 470 horsepower and 470 pound-feet of torque, considerably less than the crate engine, but still damn powerful. All of Chrysler’s performance models would eventually get this engine and in 2015, the power was upgraded to 485 horsepower, with 475 pound-feet of torque. Vehicles equipped with this great Hemi tribute engine are either badged as “6.4-liter Hemi” or “392 HEMI.”

3 6.2-liter Hellcat

797 Horsepower

HellFire can scorch, but a Hellcat tears everything to shreds. In 2015, Chrysler introduced a new high-performance Hemi engine known as the Hellcat. It was a bit of a Frankenstein engine, using the same 4.09-inch bore as the 6.4-liter Hemi as well as the 3.578-inch stroke of the 5.7-liter Hemi, giving it a displacement of 6.2 liters. It also featured a 2,380 cc twin-screw supercharger, which jammed out 707 horsepower and 650 pound-feet of torque.

6.2-liter Hellcat Models

• 2015–2023 Dodge Challenger SRT Hellcat/Hellcat Redeye
• 2015–2023 Dodge Charger SRT Hellcat/Hellcat Redeye
• 2018–2021 Jeep Grand Cherokee Trackhawk
• 2021 and 2023–2024 Dodge Durango SRT Hellcat
• 2021–2024 Ram 1500 TRX

The engine was first equipped in the Challenger and Charger SRT Hellcat models but later found its way under the hoods of Grand Cherokees, Durangos, and the mighty Ram 1500 TRX pickup. In 2019, the Redeye version of the Hellcat jacked up the output to 797 horsepower, while retaining the 707 pound-feet of torque. The name for the engine comes from the Grumman F6F Hellcat fighter aircraft and Chrysler sells it individually as the Hellcrate.

2 426 Hellephant

1,000 Horsepower

When engineers were designing the 426 Street Hemi, they nicknamed it the “elephant” not because it was slow, but rather because it was so enormous. Mopar paid tribute to the most famous Hemi, and realistically most renowned engine in the world, with the Hellphant crate engine. The homage doesn’t end at the name as this is a true modern 426 cubic inch (7.0-liter) gas-guzzling beast. Of course, thanks to modern technology, this new Hemi generates way more power than its ancestor.

Hellephant Facts

• A30 stands for aluminum block and 30-proof alcohol
• The first 100 2018 Hellephants sold out in 2 days
• Original MSRP: $29,995

Chrysler originally released a 590-horsepower 426 HEMI crate engine in 2012. There are four versions of this metallic monster, but the money engine is the A30, topped with a 3.0-liter IHI supercharger, making an Earth-shattering 1,000 horsepower and 950 pound-feet of torque. There is allegedly a variant in the works that will blast out another 100 ponies, but that might rip a hole in the time/space continuum.

1 6.2-liter Demon

1,025 Horsepower

The Demon, like the Hellcat, is a supercharged 6.2-liter Hemi, but it is a radically different engine in terms of sheer power. The Demon features a bigger 2.7-liter twin-screw supercharger, reinforced reciprocating components, a new camshaft, and various other drivetrain upgrades that pull more power out of that displacement. Running 91-octane pump gas, the Demon produces 808 horsepower and on 100-octane racing fuel, makes 840 horses.

Demonic Match-up

(Performance stats sourced from Dodge)

But wait, there’s an even more powerful variant of the 6.2-liter Demon, that was developed specifically for the Last Call Dodge Challenger SRT Demon 170. With upgrades of virtually every engine component, the Demon 170 explodes off the line with 1,025 horsepower and 945 pound-feet of torque, running on a fuel mixture of 170-proof ethanol. Running regular pump gas, the engine still makes 900 horsepower and 810 pound-feet of torque. Ironically, the Demon engine gets its name from the 1971 Dodge Dart Demon, which had a 340ci V-8 and was one of the slower Mopars of the era.