Chevrolet had both big block and small block engines under their flagship. The big block engines are a series of V8 engines developed in the States between 1950s and 1960s. Post the Second World War, American vehicles were built larger and heavier which also required stronger engines to power them. Small block V8 engines were introduced in 1955 but the country needed a larger and more powerful engine to run medium sized trucks and heavier cars that were at that time in the design stage.

The first generation of big block engines was called the W series, named after its special valve cover design. The first engine created under this series was the 409.  The 409 engine was introduced into the Chevrolet’s cars and trucks in 1958. The base model of the 409 was offered with a four barrel carburetor that wields 250 horsepower. In 1961, the Special Turbo Thrust technology gave a new life to this four barrel in which it produced 340 horsepower. Using the same Turbo Thrust technology, the 409 engine was also made available with the 280 and 350 horsepower.

The next edition in the W series was the 427 engine. It was produced in limited numbers in 1963 and later mass produced in 1966 to be installed in Camaros and Corvettes. The first 427 engines gave 430 horsepower rating but were often tuned by car owners to hit 500 horsepower. The unique 427 cubic inch version of the 409 was utilized by the Chevrolet Impala Sport Coupe. It was produced under the Chevrolet Regular Production Option Z11. Therefore, the engine is also known as the Z11 427. The Impala Sport Coupe was created especially for drag racers which include unique parts such as aluminum engine, cowl induction air system along with the 427 engine at Car Swap Meets.

 After making the 427 engine an option in Chevrolet cars, the 427 engine took a back seat until 1966 when Chevrolet developed another two versions of the 427 which was the beginning of the second generation of the 427 engine. The first version had low compression ratio of 10.25 to 1 with a four barrel carburetor offering 390 horsepower rating. The second also featured the same carburetor as the first but a higher compression ratio of 11 to 1 allowing it to push to 425 horsepower. All early 427 engines had a 3.76 inch stroke and 4.25 inch cylinder bore.

The second generation big block engine named the Mark series. At the end of the decade, Chevrolet also developed other versions of the 427 engine to offer individual 385 and 400 horsepower ratings as well as a torque rating of 460 for both. With smooth operating hydraulic lifters, the 427 was also applicable for family station wagons. 

On top of that, Chevrolet introduced the L71 427 engine between 1967 and 1969 which has three two barrel carburetors to produce 435 horsepower including 460 torque rating. A special edition of the 427 engine called the Yenko 427 was a dealer installed engine developed by Don Yenko Chevrolet. The Yenko 427 was installed under the hoods of Chevelles and Novas. Yenko 427 had a boost of horsepower from 425 to 450. A Chevy vehicle was claimed to be able to sprint from 0 to 60 miles an hour in 4.7 seconds.

Chevrolet continued producing the 427 engine up to the mid 1990s. From 1972 till 1975, the only version of the 427 available was the truck version used in Chevrolet Kodiak. From 1988 till 1995, the 427 was made available with throttle body electronic fuel injection system. Out of all the 427 LNG versions, the ZL1 engine produced in 1969 is the most highly sought after. It was developed ultimately for Can-Am racing. The ZL1 featured aluminum cylinder block which reduced the engine weight to 575 pounds ideal for a race car. However, installing the ZL1 in Corvettes which costs around $4,000 doubled the price for the car in the market.