If you stop and think about it, one engine has made motorsports in the United States for nearly 50 years. The Offy was a great engine, as was the four-cam Ford. Who can forget the mighty Mopar hemis? But the one constant through all the heydays of the engines listed above has been the Chevrolet small-block.

In 1955, Ed Cole and a group of engineers got together and brought about the foundation of modern-day auto racing at a variety of levels with the development of the original small-block Chevy. Today, it is the basis for nearly all Late Model, DIRT Modified and Sprint Car engines in competition.

Chevrolet produced its first V-8 engine in 1917, a 288-cid, 55hp model called the Series D. The engine had overhead valves and cross-flow heads, but it was a little pricey for the day. Just 2,817 examples of the engine were produced before Chevrolet called it off.

The next V-8 engine offered by the company was in 1955-model cars, and it was made available to the public on Oct. 28, 1954. As of its 40th anniversary in 1995, more than 63 million small-block Chevrolets had been produced. Untold millions of them are still on the road.

The Chevy small-block engine has been produced in 10 different displacements ranging from 262 to 400 cid. The production engine topped out at an amazing 375 hp, but race tuners have wrung upwards of 900 hp out of the package in its time.

Ahead of its Time You have to understand just how far ahead of its time this engine was when it was introduced. Thin-wall castings, stamped-steel rocker arms on spherical pivots, hydraulic lifters that metered oil to the cylinder heads by way of hollow pushrods, slipper skirt aluminum pistons, interchangeable cylinder heads with wedge-type chambers and an intake that sealed the lifter valley. Cole's sales pitch to the Chevrolet hierarchy went along the lines of, "high-performance doesn't have to mean high price." To this day, all small-block Chevy V-8 engines share their basic geometry with the original 265-cid engine produced in 1955.

Until the development of the LT1 engine in the 1990s, the small-block adapted to whatever it needed to be. In the '60s, when performance was king, it grew from its 265-cid original size to a whopping 350 cid. In the early '70s, it went to 400 cid, the largest small-block ever produced. When the energy crunch hit, the small-block was winnowed back to 262 cid. In the years since, it has standardized at 305 and 350 cid.

What does this have to do with motorsports? The development of the Chevy small-block allowed racers from several generations to compete using basically the same engine, and it allowed the tricks of the trade in engine tuning to be passed on via a somewhat level playing field. Consider sports-car racing, for instance. Every year, it seems, there are new engines coming out in different configurations. There are V-8s, V-10s and V-12s, with pneumatic valves and other high-tech applications that make the technology curve that much steeper for both mechanics and drivers, let alone the average racer who wants to work on his engine himself.

Still the One The Chevrolet small-block has been the basis for American motorsports since 1955, much as the Offenhauser was in Indy car racing from the days of the Millers and Meyer-Drakes. The difference is, according to GM Racing's Ron Sperry, you can take a modern-day SB2 engine out of a Winston Cup car and drop it directly into a 1955 Chevy without any additional drilling to get it to fit. Sperry worked with the small-block in the '60s at Chevy's Product Performance shop and was a key member of the design team on the SB2.