Buick V8 engine

Like its sister General Motors divisions, Buick produced its own family of V8 engines to replace its straight-8 engines. Some of these engines had the same displacement numbers as those from other divisions, but were entirely different engines.

Buick's first generation of V8 was offered from 1953 through 1956. It was an OHV/pushrod engine like the then new Oldsmobile "Rocket V8" engine. This engine became known as the "Nailhead" for the unusual vertical position of its small-sized valves, which were derisively compared to nails since their head diameter is smaller than other comparable displacement engines of the same era. The Nailhead V8 family used a camshaft with greater lift and duration to offset the smaller-sized valves and arguably restrictive intake- and exhaust-port diameters. The small-diameter intake runners allowed these engines to develop high torque, with many exceeding one foot-pound per cubic inch, which was exceptional for the day. All of the Nailhead designs have 4.750" Bore spacing.

The Buick V-8 was originally called the "Nail Valve" by early hot rodders because the valves looked like nails since the stems were so long and the heads were small. At some point "Nail Valve" got replaced by "Nailhead."

The 264 cu in (4.3 L) 264 was a direct replacement for the 263 straight-8 in Series 40 Buicks. It was produced in 1954 and 1955. It was the smallest displacement Nailhead, and the only engine available for the economy "Special" Series 40 through 1955. The 264 ( Bore 3.625" ) is a small bore version of the 322, sharing stroke and deck height.

The larger 322 cu in (5.3 L) 322 was used by Buick from 1953 through 1956 in the Roadmaster, Super and Century models, and finally in the Special in 1956. It had a bore of 4.00" and a stroke of 3.20".

The 322 was also used in the 1956 through 1957 Chevrolet Heavy Duty truck, the 10,000 series conventional cabs.

Buick's second variation of this V8 has also been called the Nailhead. It was produced from 1957-1966.

The 364 was introduced in 1957. The Special came standard with 2bbl carb and 250 hp, where all others had the 4bbl, 300 hp engine. Buick, like most of its competitors, continued to expand their durable V8 engine to larger displacements, such as the 364 in³ (4.125in bore)x(3.40in stroke)= 364 cubic inches (6.0 L).

...
Wikipedia