Next time I get out to the block I'll flip it around and see about by the water pump area and timing cover.

I don't recall seeing any Yenko blocks with screw-in style freeze plugs. Mine has regular plugs. I could be wrong. That block is also missing the extra headbolts. If they were machined off, I wonder why.

06017 is probably not Casting Date.
Ive seen it on other Blocks.
There was one for sale on the Corvette Forum
Casting date 030169
Tall deck
That may explain why the Block here does not have a cutouts for Sleeve flanges.
It has been decked down to short deck?

Ford Blue? Have they try to run it with Ford Heads
These cheating Ford owners

Tall deck Can Am 4.440 Bore Corvette Forum

I was told these were Yenko markings on a block I have here. Does it have stampings like these?



Jason

Siamese block that have SY Stampings and no Sleeves.

Press in frost plug

Does that block have the upside-down "LC" in the snowflake? Looks like it

I just checked the old ad I had here for my engine, and the person you want to look up is named Mark Gillepsie for decoding of those letters (he has a book for that). I think he is in Indiana. He was the jedi master of info on Yenko ZL-1 blocks. The letters decode to an engine number. All letters like yours.

I could be wrong, but 90% sure I am right. Good luck.

-bob

So no one knows what

06017

means on these blocks?

Also it's strange for the Yenko blocks, they stamp SY and not YS then 2 other letters that could be someone's initials?