1968 Early vs Late Build dates - NCRS Discussion Boards

1968 Early vs Late Build dates

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Joe M.
    Frequent User
    • February 18, 2010
    • 83

    1968 Early vs Late Build dates

    I'm tryingto interpret in 1968 what build dates are early vs late. If you can please provide any information orhelp descramble build dates between (H) and (I) build dates I would appreciateit. Are the early or late builds?

    Thanks in advance

  • Jack C.
    Extremely Frequent Poster
    • September 30, 1992
    • 1090

    #2
    Re: 1968 Early vs Late Build dates

    Joe. my 68 January 22 built car (#9643), from what has be discussed, is a very late early car. It happens to be one of the first coupes built as well. The rule of thumb was that the coupes were first manufactured around the 10,000 serial number.
    Jack Corso
    1972 Elkhart Green LT-1 Coupe 43,200 miles
    Top Flight 1994, 2018 & 2021

    Comment

    • Michael W.
      Expired
      • April 1, 1997
      • 4290

      #3
      Re: 1968 Early vs Late Build dates

      This question gets asked frequently. This might help

      https://www.forums.ncrs.org/showthre...late-breakdown

      Comment

      • Joe M.
        Frequent User
        • February 18, 2010
        • 83

        #4
        Re: 1968 Early vs Late Build dates

        Thanksfor the help Jack, I appreciate it. What I'm trying to find out is what month (ifthe timeline even exists) did they change from early to late (in the parts run)for a 1968 L71 Coupe. Theyidentify an early block 3916321 to alate block 3935439 for the year so which ones fits when? The same for the intake on the L71 as the early is 3919852 and late is3937797. The build date I'm trying to decipheris and April date. I'm getting thefeeling I'm looking for a clear cut off date which doesn't exist.

        Comment

        • Joe M.
          Frequent User
          • February 18, 2010
          • 83

          #5
          Re: 1968 Early vs Late Build dates

          Thanks for the help Michael, I appreciate it.

          Comment

          • William C.
            NCRS Past President
            • May 31, 1975
            • 6037

            #6
            Re: 1968 Early vs Late Build dates

            As GM did not use a first in-first out inventory, and from an assembly plant viewpoint no changes were required, either could have been used at the assembly plant in your timeframe it would appear, with no certainty that either was correct or incorrect.
            Bill Clupper #618

            Comment

            • Michael W.
              Expired
              • April 1, 1997
              • 4290

              #7
              Re: 1968 Early vs Late Build dates

              Originally posted by Joe Marocco (51456)
              Thanksfor the help Jack, I appreciate it. What I'm trying to find out is what month (ifthe timeline even exists) did they change from early to late (in the parts run)for a 1968 L71 Coupe. Theyidentify an early block 3916321 to alate block 3935439 for the year so which ones fits when? The same for the intake on the L71 as the early is 3919852 and late is3937797. The build date I'm trying to decipheris and April date. I'm getting thefeeling I'm looking for a clear cut off date which doesn't exist.
              I think the message here is if the engine block existed, it got used in production. I'd be hard pressed to come up with an explanation of why a part with an early date could not have been used in a car built a few weeks later.

              Comment

              • William C.
                NCRS Past President
                • May 31, 1975
                • 6037

                #8
                Re: 1968 Early vs Late Build dates

                GM used two kinds of changes to component level parts in production, coordinated changes requiring a change in the final ASSEMBLY part number or running changes where the new and old part were generally interchangable. Unless the AIM shows a change in the finished assembly part number for your engine, the assembly would not necessarily even know that a component level change had occurred. The engine group may have sent a notice of the change to the assy plant, but it would have been of little-no significance to the actual build process.
                Bill Clupper #618

                Comment

                • Joe M.
                  Frequent User
                  • February 18, 2010
                  • 83

                  #9
                  Re: 1968 Early vs Late Build dates

                  Thanks for your help Bill, I appreciate it. I guess with some of the build dates on early vs late its more of an art vs a science.

                  Comment

                  • Paul J.
                    Expired
                    • September 9, 2008
                    • 2091

                    #10
                    Re: 1968 Early vs Late Build dates

                    Originally posted by Joe Marocco (51456)
                    Thanksfor the help Jack, I appreciate it. What I'm trying to find out is what month (ifthe timeline even exists) did they change from early to late (in the parts run)for a 1968 L71 Coupe. Theyidentify an early block 3916321 to alate block 3935439 for the year so which ones fits when? The same for the intake on the L71 as the early is 3919852 and late is3937797. The build date I'm trying to decipheris and April date. I'm getting thefeeling I'm looking for a clear cut off date which doesn't exist.
                    That is correct. There might be some discussion on this in the judging manual, but I don't know for sure.

                    Comment

                    • Alan S.
                      Extremely Frequent Poster
                      • July 31, 1989
                      • 3415

                      #11
                      Re: 1968 Early vs Late Build dates

                      Hi Joe,
                      I think you can take comfort in knowing that cars often? have a few parts that seem a bit out of the time frame you might expect. (But with-in the 6 month period for most parts.)
                      My 71 base sb with a cylinder case cast on Dec. 31, 1970, and assembly date of Jan. 7, 1971 has an intake manifold dated August 1970. That's really the oddest date I've seen on my car. Next closest to odd would be the birdcage date stamp of September 1970. But since I don't know if that date is when that particular part of the birdcage was made, or if it's when the birdcage was assembled, or if it was stamped at another time, I've just been amused at even seeing it.
                      Regards,
                      Alan

                      71 Coupe, 350/270, 4 speed
                      Mason Dixon Chapter
                      Chapter Top Flight October 2011

                      Comment

                      • Joe M.
                        Frequent User
                        • February 18, 2010
                        • 83

                        #12
                        Re: 1968 Early vs Late Build dates

                        If I could ask anotherquestion. Does this tri power air cleaner lid look original to you? Thanks for the help, I appreciate it.

                        Comment

                        • Paul J.
                          Expired
                          • September 9, 2008
                          • 2091

                          #13
                          Re: 1968 Early vs Late Build dates

                          Originally posted by Joe Marocco (51456)
                          If I could ask anotherquestion. Does this tri power air cleaner lid look original to you? Thanks for the help, I appreciate it. [ATTACH=CONFIG]45487[/ATTACH][ATTACH=CONFIG]45488[/ATTACH]
                          Joe, if you don't get any responses to this question, put it in a new thread.

                          Comment

                          • Terry M.
                            Beyond Control Poster
                            • September 30, 1980
                            • 15573

                            #14
                            Re: 1968 Early vs Late Build dates

                            Originally posted by Paul Jordan (49474)
                            Joe, if you don't get any responses to this question, put it in a new thread.
                            And show a picture with more of the lid. One doesn't assess the lid solely by the hole for the attaching stud, or at least one shouldn't do that.
                            Terry

                            Comment

                            Working...

                            Debug Information

                            Searching...Please wait.
                            An unexpected error was returned: 'Your submission could not be processed because you have logged in since the previous page was loaded.

                            Please push the back button and reload the previous window.'
                            An unexpected error was returned: 'Your submission could not be processed because the token has expired.

                            Please push the back button and reload the previous window.'
                            An internal error has occurred and the module cannot be displayed.
                            There are no results that meet this criteria.
                            Search Result for "|||"