Hemi Engines Made Before the 426 Hemi
While talking to people at a Mopar event recently, the topic of the 426 Hemi came up as usual. Many of the people wanted to know how many Hemi motors were made before the 426 Hemi.
There were 12 Hemi engines made before the 426 Hemi from 1951 to 1959 produced for Chrysler, DeSoto and Dodge. They ranged in size from 241 cubic inches to 392 cubic inches. Chrysler Hemis were called FirePower, DeSoto was called FireDome and Dodge was called Red Ram and PowerDome.
The article will explain which engines came in which cars and trucks. In addition, the years each one was produced and a few pictures and videos you’ll want to check out.
The following specifications and facts were learned from my personal experience and research, Mopar engine manuals, webinars, books and articles.
Hemi Engines Made Before the 426 Hemi
The Hemi engines made before the 426 Hemi are called Generation l Hemi engines. They were produced in cars from 1951 to 1958 and up to 1959 for Dodge trucks.
Prior to 1951 Chrysler already produced hemispherical engines for aircraft and tanks. Using this technology, they produced their first automotive Hemi in 1951 called the FirePower.
The versions of the Generation l Hemis made for DeSoto, Chrysler and Dodge were all different with almost no parts in common.
The Gen 1s had different displacements, internal parts and names. The Chrysler 331 FirePower was the first one produced for Chrysler cars in 1951. Therefore, let’s start with them.
The first time I saw a first generation Hemi I was shocked. I was young and at that time I thought the 426 was the first one. I was disappointed to learn that but at the same time I wanted to learn everything about them.
Chrysler and Imperial (FirePower)
331 cubic inch FirePower
The 331 FirePower was the first Hemi Engine made by Chrysler. It has a 3.8125″ bore and 3.625″ stroke.
Most of them came with a single two barrel carburetor and were rated at 180 horsepower @ 4,000 rpm. Its torque was rated at 312 ft. lbs. The 1955 Chrysler C-300 came with two four barrels and was rated at 300 horsepower.
The 331 weighed nearly 1,000 pounds because it had the transmission bellhousing cast as part of the block.
The 331 was produced for the following cars and years:
| Engine | Car Model | Year |
| 331 | Chrysler New Yorker | 1951-1955 |
| 331 | Chrysler Imperial | 1951-1954 |
| 331 | Imperial | 1955 |
| 331 | Chrysler Saratoga | 1951 |
| 331 | Chrysler Saratoga Club Coupe | 1952 |
| 331 | Chrysler Imperial Parade Phaeton | 1952 |
| 331 | Chrysler C-300 | 1955 |
In 1958, a French car called the Facel Vega Excellence, used the 331 FirePower as its powerplant with the Chrysler automatic as an option.
In the video below there is a 1954 Chrysler New Yorker with a 331 FirePower engine.
354 cubic inch FirePower
The 354 has a 3.9375″ bore and 3.625″ stroke. The ones produced for the New Yorker and Imperial had 280 horsepower. The 300B came with 340 hp and an optional 355 hp version.
The 355 hp 354 FirePower was the first American V8 to produce one horsepower per cubic inch.
The 354 engine was also available in Dodge trucks with either one two-barrel or two four-barrel carburetors.
The 354 engine was produced for the following cars/trucks and years:
| Engine | Car/Truck Model | Year |
| 354 | Chrysler 300B | 1956 |
| 354 | Imperial Custom Crown | 1956 |
| 354 | Chrysler New Yorker | 1956 |
| 354 | Dodge D-501 | 1957 |
| 354 | Dodge C Series Pickup | 1957-1959 |
392 cubic inch FirePower
The 392 has a 4.00″ bore and a 3.906″ stroke. The actual cubic inches are 392.67. Two four-barrel versions were available with the following horsepower numbers:
- 325 hp with 9.25:1 compression.
- 345 hp with 10:1 compression.
A two four-barrel version was available for the 300C and 300D cars rated at 375 hp.
An extremely rare Bendix Electrojector fuel injection option was available on the 300D in 1958. It was rated at 390 hp but experienced reliability issues with an onboard computer.
The 16 cars produced with fuel injection were recalled to be retrofitted with carburetors.
The horsepower numbers were creeping up with the 392 which was realized by hot rodders and drag racers. Many of them used the 392 to drag race competitively.
The racers quickly caught on how the Hemi head design responded to high-octane gas. They were able to run them on alcohol and later nitromethane.
Probably the most popular was Don Garlits who was running the 392 Hemi only to be replaced by the 426 Hemi.
The 392 engine was produced for the following cars and years:
| Engine | Car Model | Year |
| 392 | Imperial Custom Crown LeBaron | 1957-1958 |
| 392 | Chrysler New Yorker | 1957-1958 |
| 392 | Chrysler 300C | 1957 |
| 392 | Chrysler 300D | 1958 |
The 392 was also installed into the French car, Facel Vega Excellence.
Find out how much an original Hemi Engine is worth in my article, The Worth of a 426 Hemi Engine.
DeSoto (FireDome)
The generation 1 DeSoto Hemis were produced from 1952 to 1957 and were called the FireDome.
276 cubic inch FireDome
The 276 has a 3.625″ bore and a 3.344″ stroke. It was rated at 160 horsepower and was produced from 1952 to 1954.
291 cubic inch FireDome
The 276 saw an increase in displacement by increasing the bore size resulting with the 291 cubic inch engine for 1955. It has a 3.72″ bore and 3.344″ stroke.
330 cubic inch FireDome
A different block than the previous two DeSoto engines. The 330 has a 3.72″ bore and a 3.80″ stroke. With a power pack option, the engine made 255 hp.
It was introduced for the 1956 model year.
Find out about the mythical 426 Hemi DOHC in my article, The 426 Hemi Dual Overhead Cam Engine – The “Doomsday Hemi”
341 cubic inch FireDome
The 341 has a 3.78″ bore and a 3.80″ stroke. The engine was used for 1956 and 1957.
The DeSoto Adventurer had two four barrel carburetors and produced 320 hp. The compression ratio was 9.5:1 and the engine used a hydraulic camshaft.
345 cubic inch FireDome
The 345 has a 3.80″ bore and a 3.80″ stroke. The 345 DeSoto Adventurer was rated at 345 hp and had 9.5:1 compression.
It was the first American car to produce one horsepower per cubic inch in a standard equipment engine.
Find out how much HP the 426 really had in my article, 426 Hemi Horsepower and Torque – Rated and Real HP.
Dodge (Red Ram and PowerDome)
The first generation Dodge Hemis were produced from 1953 to 1957 and were called Red Ram. The Dodge truck Hemis were called PowerDomes.
241 cubic inch Red Ram
The 241 was used for 1953 and 1954.
The 241 was the smallest of the early Hemi engines and has a 3.4375″ bore and a 3.25″ stroke. It has a 7.0:1 compression ratio and was rated at 140 hp.
270 cubic inch Red Ram
The 270 was used for 1955 and 1956.
The 270 has a 3.625″ bore and a 3.25″ stroke. With a 7.6″1 compression ratio it produced 183 hp with a two barrel carburetor. The Dodge Royal came with a four barrel version which produced 193 hp.
Find out if they are still making Hemis in my article, Do They Still Make a 426 Hemi?
315 cubic inch Red Ram
The 315 was used in 1956 and had 3.625″ bore and a 3.80″ stroke. The optional version of the 315, D-500, was a Hemi. The standard 315 wasn’t and came with polyspheric heads.
In addition, there was a race version called the D-500-1 which came with two four barrel Carter carburetors and an aluminum intake manifold.
Find out the real reasons why it’s called the elephant engine in my article, Why the 426 Hemi is Called the Elephant Engine.
The Firepower used to be my favorite looking early Hemi until I saw the red letters of the Red Ram Dodge.
325 cubic inch Red Ram
The 325 was produced in 1957 with a 3 11/16″ bore and 3.80″ stroke. Similar to the 315, the 325 base engine wasn’t a Hemi, its optional Hemi version, called KD-500, had two four barrels and rated at 325 hp.
Find out why the Hemi was banned twice in my article, Why the 426 Hemi was Banned From Nascar.
Read More Hemi Articles!
How Fast is a 426 Hemi? 1/4 Mile & 0-60 Results
What makes the 426 Hemi So Special
426 Hemi Specifications – Complete Engine Specs
What Hemi Means in an Engine: Generation 1, 2 and 3 Hemis
What Cars Had the 426 Hemi: Street and Race Hemis
How Much An Original 426 Hemi Car is Worth: Recent Prices
Any questions or if you have more information you’d like to contribute, send us an email found on our contact page.
Article resources
- Wikipedia: Chrysler Hemi Engine
- Don Garlits Museum of Drag Racing: Swamp Rat Gallery
- Automotive Training Center: Hemi Engines
- Hemmings: Godfather of the Hemi
- Google books: How to Rebuild and Modify Chrysler 426 Hemi Engines
