Editing Pontiac V8 engine (section)

==Design==
The 1955-up Pontiac V8 that finally reached the public was an overhead valve engine with [[cast iron]] [[cylinder head]]s and [[cylinder block|block]] and wedge-shaped [[combustion chamber]]s. An innovative design feature was mounting the [[rocker arm]]s on ball pivots on studs set into the cylinder head, rather than using a separate rocker shaft. Along with being cheaper to build, this allowed {{clarification needed span|text=more consistent valve action|reason= How can individual, unlinked rockers,• provide more consistent valve action than those ganged on a common arm? Please explain in layman's terms. Reputable citation needed.|date=May 2024}} with less weight than a conventional shaft.

All Pontiac V8s from 1955 to 1959 were reverse cooled, known as the "gusher" cooling system. It was removed from the design for the 1960 model year because designers moved the generator and the power steering pump from atop the front of the engine down to the front of the heads to accommodate a lower hoodline. However, the 1959 389 engines had the generator in front of the heads with reverse flow cooling still in use.

Pontiac differed from other GM Divisions and most other manufacturers in producing only a single sized V8 casting, rather than adding a larger [[big block]] to its line-up. The external dimensions of all their V8s, from {{cvt|326|-|455|CID|L|1}} were the same. Engine displacement is a function of bore and stroke. Pontiac's V8s share the same {{cvt|6.625|in|mm}} [[connecting rod]] length, with the exceptions of the later short deck 301, 265, and 303 Ram Air V.

Most Pontiac V8s had an overall length (to the edge of the [[water pump]] pulley) of {{cvt|28.25|in|mm}}, an overall width of {{cvt|27|in|mm}}, and a height (not including [[air cleaner]]) of {{cvt|31|in|mm}}. [[Dry weight]] ranged from {{convert|590|to|650|lb|kg}}, depending on displacement and year. Most Pontiac engines were painted light blue. The 1958 370" engine and the 1959–60 389 version was named the "Tempest" V-8 and changed in 61 to the "Trophy" V8. Pontiac in the 1950s was one of a few US manufacturers that did not regularly identify their engine names and sizes with air-cleaner or valve-cover decals.