A question of practicality

nuch_ss396 · #1 03-21-2010, 11:38 PM

Hey guys!

Been away a long time............ Glad to be back.

I have a question for the group here. Currently there is an
ebay auction for a rough cast "Yenko" ZL-1 block with steel
liners (not installed). My question is over the practicality
of such an item.

This block evidently has had no machining done to it. So how
does one get an albeit rare item like this machined for crank
and main bearing caps, camshaft bore, cylinder head bolt hole
locations, as well as all other necessary milling, drilling
and tapping?

Can even a good machine shop handle all of the necessary
machine work required? I'm sure Tonawanda had jigs and fixtures
to facilitate proper alignment for all machining operations
back in the day.......

Lastly, anyone care to hazzard a quess as to how much it might
cost to bring this rough cast block to useful life?

Nuch

**BARRY** · #2 03-22-2010, 01:08 AM

hi you would have to send it to kieth black and he would have to be set up to machine the block and if it has a factory core shift or porise block it still could be JUNK when you are all done buy a new block 4500-5200 is the way to go

**markjohnson** · #3 03-22-2010, 01:32 AM

As neat as owning a rough, un-machined ZL-1 block sounds like, I would limit it's usefulness to being a 110 LB conversation piece ONLY. By trade, I am a Machinist and there are so many major and minor operations that need to be performed on that block that you'd be looking at a HUGE investment in time and money. You are right about Tonawanda and Winters Foundries having jigs and fixtures back then to perform all these operations. You'd have to have a VERY good, Machinist set all this up again just to do ONE block and if any of these machining steps get botched or something bad happens, you could consider the block junk. Heck, I consider myself very good at what I do but even I wouldn't want to tackle something of this magnitude! One more important point is that I can't help but think that something must be wrong for this block to still be floating around for 40 having avoided machining when it was new and for the next four decades. There's a possibility that it may not have even been heat-treated yet. It may have been inspected immediately after the casting process and deemed un-machineable due to core shift or core sand or slag in the casting.

**kwhizz** · #4 03-22-2010, 02:18 AM

[ QUOTE ]
As neat as owning a rough, un-machined ZL-1 block sounds like, I would limit it's usefulness to being a 110 LB conversation piece ONLY. By trade, I am a Machinist and there are so many major and minor operations that need to be performed on that block that you'd be looking at a HUGE investment in time and money. You are right about Tonawanda and Winters Foundries having jigs and fixtures back then to perform all these operations. You'd have to have a VERY good, Machinist set all this up again just to do ONE block and if any of these machining steps get botched or something bad happens, you could consider the block junk. Heck, I consider myself very good at what I do but even I wouldn't want to tackle something of this magnitude! One more important point is that I can't help but think that something must be wrong for this block to still be floating around for 40 having avoided machining when it was new and for the next four decades. There's a possibility that it may not have even been heat-treated yet. It may have been inspected immediately after the casting process and deemed un-machineable due to core shift or core sand or slag in the casting.

[/ QUOTE ]

"Bingo"................

.....Even if you found someone to machine the block.....I'm sure the cost would be much more than a "New" GM aluminum block....

Ken

Smokey · #5 03-22-2010, 03:14 AM

I'm wondering why it didn't get machined 40 years ago. If I was a betting man, I would put money on it that they thought it was a junk casting back then...and made it into a scrap pile or the back end of someones truck.

They didn't let good casting cores slide through the cracks that easy.

nuch_ss396 · #6 03-22-2010, 09:01 AM

I've probably seen six or more of these "un-machined" rough
castings over the past 5-6 years. I tend to agree with the
suggestion that these blocks may actually be less-than-worthy;
which is why they exist in their un-machined states.

I would actually like to know the final tally if someone did
attempt/succeed with finish machining one of these.....

So is this item destined to be in a ZL-1 tribute somewhere?

Nuch

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