[johnta1]

So if the SD test car carried no partial VIN would the XD or Y8 have been assigned to the block or was it blank and what about date codes in the casting. Were these Cast with the block also or left blank.

The cast date codes were in it when the block was being poured.

I had thought that the EUN and manifest code (engine code like Y8) were stamped at the beginning of the the engine 'build'.
(73 EUN's run in order for their VIN sequence and 74 have their own sequence)

So, that engine on the lift would have a Y8 and EUN on it along with the little sticker for the assembly line guys.
But if they were sent back and reworked, how did they 'erase' the stamped info?

I looked at all the EUN's I have on SD engines.
They do not appear to have been stamped at time of engine build.
Unless the bare blocks themselves sat until ready to put in a car.
But that engine on hoist I would think should have an EUN, engine code and possibly a VIN if they had a Firebird waiting on it?

I have a lot of Y8's with a block casting dates of Kxx2.
Actually very few with a 74 cast date.

These being a very special engine and probably the only production engine to be hand built, may make this all an anomaly.