The Chevy "small block" engine was offered on an array of Chevrolet cars, including the Corvette, starting in 1955. The engine quickly became known as the "Mighty Mouse" engine because it was deceptively fast presumably because of its high compression ratio.
The photo above is a 327 small block V8 in a 1966 Corvette coupe. This particular small block was the L-79, that was really just a L-76 with a #151 hydraulic cam. This "wide-bore" engine is capable of generating 350 hp.
The 327 engine was capable of out-running many of the big blocks in its day. This was due to the favorable power-to-weight ratio that gave the mouse motor an advantage against many rivals. Today, the small block engine is known as the "mouse motor" and the big block is known as the "rat motor."
