For 58 of its 60 years, the Chevrolet Corvette has been powered by the legendary Chevrolet V-8 engine. Technological advancements have increased output threefold – from 195 hp in 1955 to 638 hp today – as well as reliability, refinement and efficiency.
However, the fundamental architecture of the Chevrolet “Small Block” remains the same today as it was in 1955: a 90-degree V-8, with overhead valves actuated by pushrods, and a 4.4-inch on-center bore spacing.
“The brilliance of the Chevrolet V-8 is its elegant, efficient design,” said Jordan Lee, global chief engineer for Small Block Engines. “The Chevy V-8 has fewer reciprocating parts, and is very efficient and has one of the best power-to-weight ratios of any engine family in the industry. The design is incredibly compact, enabling the Corvette’s signature sleek profile and low hood line.”
Despite a sporty appearance, the early Corvettes’ performance didn’t match their good looks. The car launched in 1953 with the “Blue Flame” inline six-cylinder engine and a two-speed automatic transmission – not exactly the stuff on which to build a sports car legend. That changed in 1955, when the new small-block V-8 engine became available and was ordered by 99 percent of Corvette buyers.
Not only did the new and significantly more powerful engine breathe new life into the Corvette’s driving experience, it could be linked to a three-speed manual transmission that gave the driver an even greater connection to the car. The result made the Corvette a proper sports car, and enthusiasts responded. Sales nearly doubled from 1954 and by the end of the decade, they nearly tripled.
Immediately after the V-8 was introduced, the small-block began a steady march upward in displacement, power and technological advancement.
The Corvette’s first 4.3L (265 cu. in.) small-block engine in 1955 produced up to 195 hp with an optional four-barrel carburetor. Today, the LS9 6.2L (376 cu. in.) supercharged small-block in the Corvette ZR1 is rated at 638 hp (476 kW), delivering about 230 percent more power than the original small-block engine from only 42 percent greater displacement.
Today’s small-block is also remarkably fuel efficient. For example, the 430-horsepower (476 kW) LS3 version of the Gen-IV small-block helps the 2013 Corvette accelerate from 0 to 60 mph in about four seconds, run the quarter-mile in just more than 12 seconds and achieve a top speed of 190 mph – all while achieving EPA-estimated highway fuel economy of 26 mpg.
That fuel economy compares favorably to vehicles more commonly associated with daycare drop-off vehicles than road-course lap times. Indeed, the Corvette’s highway fuel economy is better than the 2013 Hyundai Equus (23 mpg), Volvo XC90 AWD (23 mpg) or Subaru Legacy with the 3.6L flat-6 (25 mpg) – and it matches the Toyota Venza (26 mpg). It also matches or beats other sports cars with smaller engines, including the Nissan 370Z (26 mpg/3.7L V-6), Porsche 911 Turbo (24 mpg/3.8L flat-6) and BMW Z4 (26 mpg/3.0L straight-6).
Courtesy of Chevrolet
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