In need of some help. I have acquired my fathers 69 Z28 RS. My hope is to restore it back to its former glory. It was originally purchased new by my great uncle but the cars history has unfortunately been buried. The car is in rough shape now but I hope to change that over the next few years and be able to pass on to my son. I am trying to decode the block casting ID numbers to determine if it's vin matching. Obviously, this will play a huge factor in restore direction. The two block IDs are GM 34 3970010 - V1030XCD. The XCD is what seems to throw me off searching the forums. I have read that 3 digit suffixes were not applied until 1970 productions, also that the X could signify a over the counter crate motor (possible warranty). I have also read there where limited late model 69 productions that had 3 digit suffixes with the 69 SS396 included. I would think that a October 30th date would be considered late model but am still unsure of what the year even is. I would like to be sure I know what I'm dealing with before I move any further. Any input would be appreciated.

 

A 69 Z/28 block would have a DZ suffix code. What you have there is an over the counter, 350 crate engine. Look at the top of the bellhousing flange, there should be a date casting either in the center or on the passenger side. Since there was no mention, I take it there isn't a partial VIN stamped on the front pad? That further supports the non original/crate engine status.

 

As Senior Mod suggests, the engine, block at least, may be a warranty replacement as some '69 DZ's had high oil consumption.

My hometown had two DZ's with service replacement blocks, both DZ's used 8 qts of oil in 120 miles. GM suggested the rings were too hard for seating.

Replacement blocks could be 3970010 as the block was from '68 through '79.
Date on casting will tell.

 

This site is excellent and so is how the subject matter was explained. I also like some of the comments too.Waiting for next post.

 

Sorry it took me a few days to get back. The only other stamping a I can find on the block appears to be J242. Took photos of the others stamps but am unable to load them via phone. There is a T N D with a dial pointing to the D as well as a dial with circle dots around it pointing to a 4-5 o'clock area of dots. Thank you for the help and quick responses!

 

Was that J242 on the bellhousing flange? That would be the date code then.
(A-L = 1-12) J=the 10th month, October. 24 is the day of the month. 2 is the year, 1972. In that case, it's not a 69 Vintage block, and definitely never was a 302.

 

Thank you again. It may sound stupid but I am happy that it is not matching. My budget could not afford a legit restore. That, and I have my mind set on going back to what my father had it to and taking it back to upstate New York for a few more passes down memory lane. I'm sure i will be frequenting this forum over the next few years and appreciate you help!

 

As long as you know for sure the car is in fact a Z/28, you still have that at least.