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General Discussion => GS Questions => Topic started by: Dr Frankenbuick on April 13, 2013, 06:12:34 AM

Title: Engine Code Question
Post by: Dr Frankenbuick on April 13, 2013, 06:12:34 AM

I understand the basic engine codes related to year, size and designation, but do not understand the three number code after the letter code.  My car was built in the first week of August in 65 and has a Protect-O-Plate with matching numbers.  The 242 on the NK 242 transmission makes sense as date code, but the 599 on the LR 599 engine and Protect-O-Plate does not seem to be related to any date or shift code even close to August. Does anyone know how the three numbers after the two letter engine code break down into a date code?

Thanks - Steve   

Title: Re: Engine Code Question
Post by: WkillGS on April 13, 2013, 08:11:04 AM

I've heard a few theories.
One was it was a 'day' code, but a 2-year cycle.
The other was it's the shift number, with #1 being the first shift of the first day of the production year, #2 being the 2nd shift of the first day, etc.
If you figure production started Sept 1964, and they worked 26 days a month with 2 shifts per day,
August would be about 572 shifts in, so your '599' is in the ballpark.

Were all Buick engines built in the same plant at Flint?

Title: Re: Engine Code Question
Post by: Dr Frankenbuick on April 13, 2013, 04:20:46 PM

It could be the second option Walt.  It would not work as a a two year date code.  I guess I was thinking the engine date code would start in the actual year built (like the transmission code) instead of going back to the beginning of the production run.  This issue has always bothered me when looking at any nailhead engine code.

Thanks