330 HP 454 Specsby John Willis
During the American Muscle Car era of the late 1960s to the early 1970s, Chevy developed a series of engines, commonly referred to as "Big Blocks." In 1970, Chevy rolled out an enormous 7.5-liter, 454-cubic-inch big block, V-8. A V-8 of this size can easily be setup to generate in excess of 500 horsepower. While the 454 was used in high-horsepower cars such as the Corvette and Chevelle, the Chevy 454 automobile engine made 330 horsepower stock. Chevy's parent company, General Motors, adapted the 454 automobile engine into the 330-horsepower, 454 marine engine.
GM Marine Engines
Based on the same 454-cubic-inch big block Chevy, General Motor's Marine Engine division set up the motor specifically for use in boats. Because General Motors was not a boat maker, but a motor and automobile maker, their marine engines division often sold parts to companies specializing in setting up marine engines such such as Mercruiser.
The 330-horsepower, marine 454 is different from the 454 automobile engine from which it was derived. Because boats have just one gear and very different power and torque requirements, everything that shapes power and torque characteristics are different: compression, valve-train, intake and headers. Water pumps for marine engines are specifically designed to withstand corrosion because the systems use open water for cooling and may contain salt, minerals and all kinds of chemicals. Marine carburetors are also designed so that fuel delivery is uninterrupted despite the extreme pitch of the boat during cornering. All electrical components must be able to withstand a hostile, wet environment.
454 Marine Specs
The GM marine 454 had a bore of 4.25 inches and stroke of 4 inches with compression ratio of 8.1-to-1. The engine breathed through a four-barrel carburetor, and ignition was provided by a Delco Electric unit. The marine 454 weighs 980 lbs and makes 330 horsepower, at its maximum RPM of 4,400.