Chrysler Firepower: The History Of The First Hemi Engine

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Stellantis, nan genitor institution of Chrysler and RAM, caused rather a ruckus successful 2024 erstwhile it announced it would discontinue nan legendary HEMI motor successful its RAM trucks. However, the blowback from this alteration prompted nan institution to quickly reverse course, and successful 2025 it was announced that nan HEMI would beryllium reintroduced successful nan 2026 RAM. In nan property merchandise distributed by Stellantis, nan CEO of nan RAM marque Tim Kuniskis moreover called discontinuing nan HEMI a "mistake".

Perhaps it was — aft all, this iconic powerfulness works has been beloved ever since nan 1951 accumulation debut of the FirePower, Chrysler's very first HEMI engine. However, nan existent history of nan HEMI goes overmuch farther backmost than that. In fact, it starts astir half a period earlier nan Chrysler FirePower ever saw nan ray of day. A HEMI motor would triumph a Grand Prix and different 1 would subordinate nan Allies successful World War II well earlier Chrysler would commencement utilizing it successful its accumulation automobiles.

While nan sanction HEMI is intimately associated pinch Chrysler and different members of its family of brands — astir notably Dodge and RAM — nan automaker did not invent nan engine, moreover though it would yet trademark nan name. Here's nan afloat history of nan HEMI legacy.

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The very first HEMI motor was apt utilized to powerfulness a boat, and nan first HEMI motor utilized successful a car was only a 4-cylinder. Though location is not a clear consensus, galore historians in installments Chelsea, Wisconsin resident Allie Ray Welch pinch inventing nan concept. He built a two-cylinder prototype successful 1901 and utilized it arsenic nan centrifugal for a boat.

The first clip an automaker put 1 successful a car was successful 1905, by a Belgian institution named Pipe.  A small later, nan Premier Automobile Co, of Indianapolis would spot a HEMI motor successful a title car. The Premier could crank retired 100 hp astatine 1,000 rpm. Due to nan weight of its engine, nan car would beryllium disqualified from each but 1 race, contempt nan champion efforts of its proprietor Carl Fisher. That title was astatine nan Indiana State Fair, wherever it won by reaching nan alarming velocity of 59 mph.

Other manufacturers, for illustration Fiat, Peugeot, Alfa Romeo, Daimler, and Riley would besides commencement producing cars pinch HEMI engines successful nan first portion of nan 20th century. Felice Nazzaro drove a HEMI-equipped Fiat to triumph successful nan 1907 Grand Prix, winning that title by complete six minutes. The HEMI design, aliases variations of it, have been utilized successful title cars since then.

The entreaty of nan motor came for its earthy powerfulness and unsocial design. The cylinder caput combustion chambers connected nan early HEMI engines were shaped for illustration one-half of a sphere, aliases hemisphere — hence nan name, HEMI. This makes it imaginable to spot nan spark plug apical and center, which makes nan pain of nan air/fuel substance much efficient. Air flow, meanwhile, is improved by nan placement of an intake and exhaust valve connected either broadside of nan plug.

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Some shape of nan HEMI motor would popular up present and location aft nan early years of nan 20th century, but Chrysler had yet to adopt it. That would alteration during World War II. American automotive manufacturers shifted their attraction dramatically from producing civilian automobiles to nan warfare effort. Entire automotive plants would beryllium converted to factories for making tanks, subject vehicles, and moreover airplane engines.

Chrysler was nary objection successful this regard, arsenic it would build 22,000 tanks complete nan people of nan war. Also notable among Chrysler's efforts during nan warfare was nan improvement of nan experimental 2,500-hp 36.4-l inverted V16 craft engine, which was, successful fact, a HEMI. It was tested successful a Republic P-47 Thunderbolt to awesome success, reaching complete 500 mph. 

However, nan warfare ended earlier it could beryllium rolled retired to accumulation and pitchy engines beautiful overmuch made it obsolete. Chrysler would enactment successful nan subject instrumentality business aft nan warfare ended, however, by producing nan V-12 AV-1790-5B motor for nan cold-war era M47 Patton tank.

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Chrysler put to usage nan knowledge it had gained during World War II and introduced its first V8 HEMI automotive motor in 1951. Interestingly, immoderate opportunity that neither this motor — nor immoderate of nan modern Chrysler HEMIs — are existent HEMIs. This is because alternatively of utilizing genuinely hemispherical cylinder caput combustion chambers for illustration nan original HEMIs, Chrysler decided to spell pinch a smaller dome shape. That motor wasn't moreover called HEMI astatine first — instead, it was fixed nan sanction FirePower and internally referred to arsenic nan Double Rocker due to its dual-valve configuration.

The automaker put nan FirePower engine successful 3 of its cars, nan Chrysler New Yorker, nan Chrysler Imperial, and the Chrysler Saratoga. It measured 331 cubic inches and was rated astatine 180 hp. That would beryllium humble by today's standards, but nan Chrysler HEMI outclassed its nearest competition, nan 1951 Cadillac, by 20 hp.

Chrysler was truthful assured successful nan FirePower that it asked nan different brands successful nan family to create their ain lines of HEMI engines. Soon, DeSoto would nutrient nan Firedome starting successful 1952 and Dodge would merchandise nan Red Ram starting successful 1953. While similar, these engines were each developed separately, arsenic was nan believe among sister brands astatine nan time, which meant that their parts were not interchangeable.

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Chrysler had thrown down nan gauntlet, but different automakers quickly picked it up. Cadillac slapped a 4-barrel carburetor to nan motor it installed successful its 1952 Series 62, boosting output to 190 hp. Meanwhile, Ford would show up nan Chrysler FirePower pinch large wins for nan Lincoln astatine the Carrera Panamericana endurance title successful 1952, 1953, and 1954.

Lincoln's wins connected nan racetrack were getting headlines, leaving Chrysler's estimation astatine stake. It would respond successful 1955 by releasing nan Chrysler 300, which was fitted pinch a FirePower HEMI motor that was rated astatine an astounding 300 hp. By 1958, title had pushed Chrysler to nutrient nan 300D configuration for nan 392-cubic-inch FirePower V8 engine, which could crank retired 380 hp — nan highest successful nan manufacture astatine nan time. 

Consumers could besides opt for a high-performance type of nan motor paired pinch a manual transmission that was rated astatine 390 hp, though immoderate experts estimate that it could really scope 435 to 450 hp. Unfortunately, this would beryllium nan past accumulation exemplary equipped pinch a FirePower. Sales had dropped, and nan institution decided to pivot from HEMI engines to lighter, more businesslike wedge-head V8 engines, which were much cost-effective to manufacture.

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The FirePower's racing history began successful 1951, erstwhile Tom McCahill drove a Chrysler New Yorker astatine Daytona Beach and won the trophy for nan fastest American banal car. After nan 1954 Indianapolis 500, Chrysler revealed its 331 cubic inch HEMI engine, which could execute arsenic good arsenic nan apical vehicles successful nan title that year. However, Indy officials froze HEMI engines retired later that twelvemonth by decreasing nan size limit of engines to 272 cubic inches.

Chrysler returned successful 1955 pinch a fleet of Chrysler 300 ace coupes. That twelvemonth would spot that team's prima driver, Tim Flock, triumph 18 races, including nan championship. Buck Baker would triumph 14 races for nan squad successful nan pursuing year. What's more, nan squad would triumph 16 races successful a statement successful 1956.

Chrysler would discontinue its accumulation and racing Firepower engines successful 1958, but racing would punctual Chrysler to resurrect nan HEMI motor successful 1964, erstwhile it created its Gen II HEMI motor to compete successful NASCAR. It would predominate nan Daytona 500 that year, prompting NASCAR to enforce a norm that would restrict Chrysler from utilizing that type of nan HEMI motor until it had sold street-legal accumulation models. Chrysler would respond by producing 1966 B-body Dodges and Plymouths pinch street-legal HEMI engines.

The Chrysler FirePower has some a storied history and powerful legacy. Its successors, nan Gen II and nan existent Gen III HEMI engines, would go integral parts of nan company's exemplary lineup. Sadly, nan ICE-powered, HEMI-equipped Dodge Charger and Challenger were discontinued successful 2023 successful favour of EV versions — but astatine slightest nan HEMI motor will unrecorded connected successful upcoming RAM trucks.