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Where is the Chart to decode 455s “Date Codes”?

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Old May 13, 2026 | 07:55 AM
  #1  
Texas442's Avatar
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1971 442 conv
 
Joined: Jun 2009
Posts: 908
From: Austin, Texas
Where is the Chart to decode 455s “Date Codes”?

Can someone tell me where I can find the chart that explains how to decode the “Date Code” near the distributor engine block?
I've got a couple of blocks to decode before posting 1 of them for sale and keep the other.
For example: What is the date code for this 455? What is the "4" means?
.



Old May 13, 2026 | 10:31 AM
  #2  
1965CutlassGuy's Avatar
9 thats what I mean 11
 
Joined: Nov 2023
Posts: 209
From: Oregon
4 is the mold number.
222 is Aug 10
They should have a VIN derivative stamped on the drivers side front of the block which would give you the year of the car it was in.
396021F with a plain F is 1968-1970
396021F with a Serif type F is 1970 to 1972
396021Fa is 1972 to 1976



Old May 14, 2026 | 05:41 AM
  #3  
joe_padavano's Avatar
Old(s) Fart
 
Joined: Mar 2007
Posts: 50,802
From: Northern VA

Old May 14, 2026 | 10:52 AM
  #4  
Texas442's Avatar
Thread Starter
1971 442 conv
 
Joined: Jun 2009
Posts: 908
From: Austin, Texas
Thank you both very much!! That is exactly the information I was looking for.
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