What Engine Came in the Dodge Charger RT

The Dodge Charger RT came with a 440 cubic-inch V8 engine as standard equipment during its peak production years from 1968 to 1971. This engine produced 375 horsepower in 1968 and 1969, then increased to 390 horsepower in 1970 and 1971. The 440 was a big-block engine designed for straight-line performance and muscle car competition.

A 426 Hemi V8 was also offered as an optional upgrade, though it cost significantly more and was less common. The Hemi produced 425 horsepower and became the most sought-after variant among collectors today. Both engines used a carburetor fuel system and were paired with either a three-speed automatic or four-speed manual transmission, depending on the model year and buyer preference.

After 1971, Dodge discontinued the original Charger RT nameplate for several years. When the Charger returned in later decades, engine options changed with emissions standards and market demand. The modern Charger RT (2015–2023) used a 5.7-liter V8 producing 370 horsepower, a completely different engine family from the original.

Key Takeaways

  • The classic Charger RT (1968–1971) came standard with a 440 cubic-inch V8 producing 375 to 390 horsepower depending on the year.
  • A 426 Hemi V8 was available as an expensive option and is now the most valuable and collectible variant.
  • Both engines were paired with three-speed automatic or four-speed manual transmissions.
  • Modern Charger RT models use a 5.7-liter V8 with different horsepower ratings and fuel injection instead of carburetors.

440 Big-Block Engine Specifications

The 440 cubic-inch engine displaced 7.2 liters and featured a cast-iron block with two valves per cylinder. It ran on regular unleaded gasoline and used a four-barrel carburetor to mix fuel and air. The engine sat longitudinally in the engine bay, mounted on rubber isolators to reduce vibration transferred to the frame.

Horsepower and torque figures varied slightly by year and tune. The 1968–1969 versions produced 375 horsepower at 4,600 RPM and 480 pound-feet of torque at 3,200 RPM. The 1970–1971 models were rated at 390 horsepower at 4,700 RPM and 500 pound-feet of torque at 3,200 RPM. These numbers reflected changes in how manufacturers measured power output and minor tuning adjustments to meet evolving emissions rules.

Cooling the 440 required a large radiator and heavy-duty fan. The engine ran hotter than modern engines because it lacked the thermal management systems found in contemporary vehicles. Oil capacity was typically 5 quarts, and the engine consumed oil at a rate that required checking the dipstick every few hundred miles during normal driving.

426 Hemi Engine and Rarity

The 426 Hemi was Dodge's ultimate performance option for the Charger RT, though only a small fraction of buyers ordered it. The Hemi designation referred to the hemispherical combustion chamber shape, which allowed larger valves and better airflow than the standard 440. This design made the Hemi more efficient at high RPM, where muscle car performance was measured.

The 426 Hemi displaced 426 cubic inches (7.0 liters) and produced 425 horsepower at 5,000 RPM and 490 pound-feet of torque at 4,000 RPM. It used a dual four-barrel carburetor setup, meaning two separate carburetors fed the engine instead of one. This configuration required a special hood with a functional air scoop to clear the tall intake manifold.

Hemi-equipped Chargers cost roughly $600 to $800 more than the base 440 model in 1968 dollars, a substantial premium when the entire car cost around $3,500. Insurance companies also charged higher premiums for Hemi cars. As a result, Hemi Charger RTs are rare today—fewer than 500 were built across all production years—and they command prices two to three times higher than comparable 440 models on the collector market.

Transmission Pairing and Driveline

The 440 and 426 Hemi engines were matched to either a Torqueflite three-speed automatic or a four-speed manual transmission. The Torqueflite automatic was Chrysler's in-house design and featured a fluid torque converter instead of a mechanical clutch. It shifted smoothly but was heavier than the manual and reduced fuel economy slightly.

The four-speed manual was a Chrysler A833 unit with a floor-mounted shifter. It allowed drivers to control gear selection directly and was preferred by performance enthusiasts who wanted to maximize acceleration. The manual transmission reduced weight and improved fuel economy compared to the automatic, though it required more driver effort in stop-and-go traffic.

Both transmissions sent power to a solid rear axle with a limited-slip differential. The differential allowed the rear wheels to rotate at different speeds during cornering while still delivering power to both wheels during acceleration. Gear ratios ranged from 3.23:1 to 4.10:1 depending on the model year and buyer preference, with higher ratios providing quicker acceleration but lower top speed.

Fuel Consumption and Operating Costs

The 440 and 426 Hemi engines were not designed for fuel economy. Real-world fuel consumption ranged from 9 to 12 miles per gallon depending on driving habits, road conditions, and carburetor tuning. Highway driving at steady speeds yielded better mileage than city driving with frequent acceleration and braking.

Both engines required regular maintenance that added to operating costs. Spark plugs needed replacement every 10,000 miles, and the carburetor required periodic cleaning and adjustment. Oil changes were recommended every 3,000 to 5,000 miles, and the engines consumed oil between changes—a quart every 500 to 1,000 miles was not unusual for a worn engine.

Fuel tank capacity was 20 gallons, which meant frequent fill-ups during highway trips. At 10 miles per gallon, a full tank provided only 200 miles of range. This was acceptable in 1968 when gas stations were common and fuel cost roughly 35 cents per gallon, but it became a significant consideration as fuel prices rose through the 1970s.

Modern Charger RT Engine Comparison

The Charger RT nameplate returned in 2015 with a completely different engine. The modern version used a 5.7-liter V8 producing 370 horsepower and 395 pound-feet of torque. This engine was smaller in displacement than the original 440 but produced similar horsepower through fuel injection, variable valve timing, and computer control.

The modern engine was far more efficient, achieving 16 to 18 miles per gallon in mixed driving—roughly double the original Charger RT's consumption. It required oil changes every 10,000 miles instead of every 3,000 to 5,000 miles. Spark plugs lasted 100,000 miles, and the engine produced significantly lower emissions while meeting modern safety and environmental standards.

The modern Charger RT also offered an optional 6.4-liter V8 producing 485 horsepower, which was closer in spirit to the original muscle car philosophy. However, even this high-performance variant used fuel injection and computer management, making it vastly more reliable and easier to maintain than the carbureted engines of the 1960s and 1970s.

Finding Engine Information on Your Charger RT

The engine size is stamped on the block itself and visible when you open the hood. On classic Charger RTs, look for casting numbers on the passenger side of the block near the bell housing. These numbers identify the engine's production date and original specifications.

The Vehicle Identification Number (VIN) also encodes engine information. On 1968–1971 Chargers, the eighth digit of the VIN indicates the engine: "T" meant 440, and "J" meant 426 Hemi. The original window sticker, if available, lists the exact engine and transmission combination ordered from the factory.

For modern Charger RTs, the owner's manual specifies the engine size and horsepower rating. The VIN also contains this information, and Dodge dealerships can decode it using the vehicle's identification number. Service records and maintenance logs often document engine work and modifications over the vehicle's life.

Frequently Asked Questions

How much horsepower did the original Charger RT engine really have?

The 440 produced 375 horsepower in 1968–1969 and 390 horsepower in 1970–1971. The 426 Hemi produced 425 horsepower. These were manufacturer ratings measured on a dynamometer, though real-world output varied depending on carburetor tuning, ignition timing, and fuel octane.

Is the 426 Hemi better than the 440?

The Hemi made more horsepower and revved higher, making it faster in a straight line. The 440 was cheaper, more reliable, and easier to maintain. For collectors, the Hemi is rarer and more valuable, but both are respected engines in the muscle car community.

Can I swap a modern engine into a classic Charger RT?

Yes, engine swaps are common among enthusiasts. A modern 5.7-liter or 6.4-liter V8 fits the engine bay with modifications to the motor mounts and cooling system. The swap improves reliability and fuel economy but requires rewiring the electrical system and may affect the car's originality and collector value.

What fuel octane should I use in a classic Charger RT?

The original 440 and Hemi engines were designed for 91 to 93 octane fuel. Modern 87-octane regular fuel may cause pinging or detonation, especially under load. Using the correct octane prevents engine damage and ensures the carburetor tuning works as intended.

How do I know if my Charger RT has the original engine?

Check the casting numbers on the block, the VIN code, and the original window sticker if available. A Dodge specialist or classic car appraiser can verify authenticity by examining the engine's date codes, bolt patterns, and component markings. Service records also document whether the engine has been replaced.