How much horsepower does a 1973 Dodge Challenger 440 have?
The horsepower values for a 1973 Challenger with a 440 engine vary by configuration, but typical figures are about 275–290 hp for the 440 four-barrel and roughly 335–350 hp for the 440 Six-Pack. Exact numbers depend on the specific build, emissions equipment, and carburation.
In this article, we’ll break down the common 1973 Challenger 440 variants, explain how horsepower was rated at the time, and outline how to verify the precise figure for a given car. Horsepower ratings from the era reflect SAE net horsepower, which accounts for accessories and emissions controls, and can differ from other measurement methods used in earlier years.
Variants and horsepower figures
The following figures reflect typical SAE net horsepower ranges for the 1973 Challenger 440 configurations. They illustrate how power differed between a standard 440 and the performance-focused Six-Pack option.
- 440 cubic inch V8 with a single four-barrel carburetor: approximately 275–290 horsepower (SAE net)
- 440 Six-Pack (three two-barrel carburetors): approximately 335–350 horsepower (SAE net)
Because of emissions equipment, tuning, and model year variations, individual cars can show a slight deviation from these ranges. The factory build sheet remains the most reliable source for a given vehicle.
Notes on horsepower ratings
During the early 1970s, horsepower ratings shifted to SAE net measurements, which reflect power after belt-driven accessories and exhaust were connected. The 440 Six-Pack typically carried a higher rating than the standard 440, reflecting its more aggressive cam and carburetion. Fans and collectors should be aware that marketing horsepower and showroom numbers can differ from the numbers you’ll find on a specific car’s documentation.
How to verify horsepower on a specific car
To confirm the exact horsepower of a particular 1973 Challenger 440, start with the original documentation and identifiers associated with the car. Useful sources include the broadcast sheet, build sheet (V.I.N.-linked), and the window sticker. If possible, consult a Mopar specialist or a restoration guide that cross-references engine codes and carburetor configurations for 1973 Challengers.
Real-world dyno testing can provide a practical picture of current power, but readings may differ from factory ratings due to wear, tuning, and modifications over time. For historical accuracy, prioritize original documentation and reputable reference works.
Summary
In the 1973 Dodge Challenger lineup, horsepower for the 440 engine ranged from about 275–290 hp with the standard four-barrel setup to roughly 335–350 hp with the Six-Pack option. Exact figures depend on the car’s specific build, carburetion, exhaust, and emissions components, making the build sheet the best way to confirm a particular vehicle’s output. The era’s SAE net ratings are the guiding standard for these numbers, and researchers and enthusiasts should consider documentation and context when assessing a specific Challenger’s power.
