Chevy 427 Horsepower Specsby Rob Wagner
The Chevrolet 427-cubic-inch, V8 engine debuted in limited numbers in 1963, but it wasn't mass-produced until 1966. Chevrolet used performance 427s in Corvettes and Camaros, and it used lower horsepower versions in family station wagons.
Chevy's first 427 generated 430 horsepower, but it often was tuned to produce 500 horsepower. Chevrolet sold it in 1963 as an option. The 427 went on hiatus until Chevy developed two other versions in 1966. One was the low-compression (10.25:1 compression ratio) four-barrel carburetor generating 390 horsepower and 470 pound-feet of torque. The other featured a four-barrel carburetor and a 11:1 compression ratio that produced 425 horsepower and 460 pound-feet of torque. All 427s featured a 4.25-inch cylinder bore and 3.76-inch stroke.
By 1967, Chevrolet offered horsepower ratings of 385 and 400 on two 427s, with the torque rating for both at 460 pound-feet. The 425-horsepower 427 remained untouched. However, Chevrolet introduced its L71 427 with three two-barrel carburetors to generate 435 horsepower and 460 pound-feet of torque.
The Yenko 427 was a dealer-installed 427-cubic-inch V8 developed by Don Yenko Chevrolet and placed in Camaros, Chevelles and Novas. Yenko boosted the horsepower from 425 to 450 with the same torque rating at 460 pound-feet. A Chevy equipped with a Yenko 427 could go from 0 to 60 mph in 4.7 seconds.