Chrysler's Infamous HEMI
Hemi stands for HEMIspherical Combustion Chamber. Which means the shape of the chamber is shaped like a half sphere. The HEMI was manufactured for the years 1966-1971.The HEMI was a 426 cubic inch engine. It had massive horsepower,425 to be exact and that was an underrating, which made it unbeatable on the road and on the track. So unbeatable that NASCAR banned it. Now that is how powerful the HEMI really is.
History of the HEMI
The 426 Hemi-head engine was designed and built with an extremely short deadline, but that didn't stop it from being possibly the most well-built piece of machinery ever put into an automobile. The engine had a max vertial separating load of 18,800 lb @ 7200 rpm along the crankshaft centerline, meaning durability was going to be crucial. Frank Bialk was given the job of designing the new main-bearing caps, which he took advantage of the deep-skirt walls by adding cross-bolts through the block into the caps. With this addition, the engine-block skirt helped the main-bearing caps in resisting the loads. Bolting the heads to the block is crucial in getting the maximum power out of the engine. The Hemi heads were designed with an extra bolt, the fifth head bolt, to give it that extra strength it needs. The position of the fifth bolt was going to be directly in the way of the pushrods and intake port, which would cause a definite restriction in power. Again Frank Bialk came up with the design of bringing the bolt up from the bottom instead. The new pattern worked very well, and the Hemi engine was put into production.
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