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Big block high & low decks, hemi & wedge gas engines

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I knew that big block wedge engines came in a high deck & low deck (including 361, 383 I'm familiar with) but have just been reading up on the 354 hemi (low deck) vs 426 hemi (high deck). There's more to earlier low deck Hemis which were made in brand specific, non-interchangeable series of different hemi blocks, not just being made in 2 deck heights! High & Low deck engines within the same brand use different cams to keep the valve train angles correct.The Hemi was introduced in 1951 in Chrysler branded cars (LD:331, 354, HD: 392). In 1952 DeSoto brought out their own Hemi (276, 291, 330, 341) And in 1953 Dodge brought out it's own Hemi (241, 270, 259, 315, 325, 331, 354). For the most part, these were separate, non-interchangeable products & parts. (DeSoto & Dodge were smaller displacement... with the cylinders closer together. No Plymouth got a Hemi until 1964. While the hemi head design was revived, the 426 Hemi is a distincly different design with the distributor in front. The famous "Street Hemi" version came out in 1966 in order to qualify for NASCAR racing as a production engine. Wedge head engines began to replace Hemis in 1958. The "high deck" A block (383 {1958-1960}, 413, "426 wedge", 440). The B "low deck" block appeared concurrently beginning the same year (350, 361, 383 {1962-1971}, 400) all sharing the 3.375" stroke.So the 361 ('64 Chrysler) & 383 (68 Roadrunner, 69 Chrysler) were both B block (big block, low deck) engines.

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