56 Valve Springs`

[Bruce L. Wiley]

Does anyone know the original GM part numbers for the Valve Springs and Valve seals? Thank you.

[Roger A. Zimmermann @21015]

The valve springs had the number 146 3226 for intake and exhaust at the beginn of MY; then the number changed to 146 5408, used until 1965.
The seal had the part number 145 3923. Used from 1949 to 1965.

Roger

[Warrren Rauch]

 A seemingly easy question. Not. THere were a lot of changes made as running changes at this time, this was one. The seals were the same (1957 book) 49-57 part#1453923. The springs
  1953-1955, 1956 To engine unit #(located on rear of block behind left cyl. head)before 4x-22788,4xk-7453,5x-475,5xk-22,7x-1999,7xk-1266,56s-71 and after56s-950. spring #1459741.
 late1956 starting with the above numbers and including 56s-71 to56s-950 as well as all 1957 (57 book) spring #1465408
 Note the early ones have a daub of yellow paint the later ones white paint.
  For the curious:

          outside dia 1 7/32 both
          free length  1 63/64 early 2  1/4 late
          compressed length 1 9/32 early  1 1/2 late
          test (pounds)  152-162 early   155-165 late
Warren