I’m picking up a 69 gto convertible  to let,  sight unseen other than pics and info from a reliable seller. He says that the engine numbers seems to date the motor 8 or 9 months prior to the date  the VIN. Is that possible and if so, is there a correlation between the stamped engine number and the VIN. If so, where is that particular number located.

There are two stamp pads on the front of the engine block. On one side you have a nine digit number that starts with a "2" (for Pontiac), "8" (for 1968), "R" (for Arlington TX plant) with the remaining six digits being the last six numbers of the cars VIN. This is a pic from my late great 1968 GTO...

You can see they match the last eight numbers of the VIN (highlighted in yellow)...

 

The pad on the other side of the front of the block has the engine production number and a two letter code that identifies the engine and the transmission (manual or automatic). Mine was a "WS" code for 400 HO/manual...

Thanks for the help. I have the car and will be looking for that number tomorrow. Another question. I’m looking for a good site to decode the data plate. I’ve been on three different sites and none of them seem to look exactly like my plate. Any idea why that would be and maybe a reference for a new site. Thanks again for your help.

If you can post a clear pic of the data plate... I'm sure that accurately  decoding it will be no problem.... 

Welcome to Forever Pontiac...

Edited February 10, 20215 yr by TWO LANE BLACK TOP

On 2/4/2021 at 7:45 PM, Mike l said:

I’m picking up a 69 gto convertible  to let,  sight unseen other than pics and info from a reliable seller. He says that the engine numbers seems to date the motor 8 or 9 months prior to the date  the VIN. Is that possible and if so, is there a correlation between the stamped engine number and the VIN. If so, where is that particular number located.

Everything TWO LANE has mentioned is spot on. In regards to the question is it possible that the engine can be 8-9 months older than the car, yes in theory. Remember that all sub-assemblies have to be built prior to the final assembly of the car. Since Pontiac V8s were made in the Pontiac Michigan engine plant and then shipped to the various Pontiac GTO assembly plants in Pontiac (MI), Baltimore (MD), Fremont (CA), Kansas City (MO), Framington (MA), these engines could sit in the assembly plant's engine inventory for quite some time before being used. They did not use just-in-time inventory control in those days.

On 2/9/2021 at 10:24 PM, Mike l said:

Thanks for the help. I have the car and will be looking for that number tomorrow. Another question. I’m looking for a good site to decode the data plate. I’ve been on three different sites and none of them seem to look exactly like my plate. Any idea why that would be and maybe a reference for a new site. Thanks again for your help.

In addition to decoding your data plate, you should send your VIN to PHS Services to get a copy of the original invoice to see exactly what options were on your GTO when it left the factory. Money well spent.

http://www.phs-online.com/services.htm