Yenko aluminum block

[bergy]

This old thread was linked on another site recently & it really brought back memories. We made the cores for these blocks at the Chevrolet Tonawanda Foundry & sent the pattern equipment over to Lockport for aluminum casting. Then the blocks came back to Tonawanda for machining on a special CNC machine that was located up by the doors leading to the main offices. The machine was very advanced at that time & the tolerances were much closer then the regular production equipment. The whole operation had to be quarantined because the aluminum machining chips couldn't get into the regular production chips (aluminum causes pin holes to occur in cast iron). I realize that the ZL-1 option was very expensice, but these blocks cost Chevrolet a fortune to produce! Also, theft was a problem - another whole story! My recollection is that the CNC machine was still in place at least through 1978.

[Xplantdad]

Neat info Bruce!

[black69]

Here is a ZL-1 block that is similar to the one I have, and has similar attributes to what is described in this thread.

I will be watching it to see where it ends up. With that casting number, it can be considered for use as is in FAST/purestock drags, as an FYI.

http://www.ebay.com/itm/1969-ZL-1-ALUMIN...=item256bded370

[Charley Lillard]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: black69</div><div class="ubbcode-body">Here is a ZL-1 block that is similar to the one I have, and has similar attributes to what is described in this thread.

I will be watching it to see where it ends up. With that casting number, it can be considered for use as is in FAST/purestock drags, as an FYI.

http://www.ebay.com/itm/1969-ZL-1-ALUMIN...=item256bded370 </div></div>

I think this is the first time I have ever seen somebody use grade 8 bolts on a intake manifold.

[COPO_Anders]

I assume the ZL-1 blocks in this thread are of the same type as the ones put in the 1969 ZL-1 Camaros at the factory. That is, they where not beefed up like the Yenko-blocks from the last half of the seventies that could take more pounding, right ?

[img]<<GRAEMLIN_URL>>/hmmm.gif[/img]

[black69]

I think each guy (Ed Cunneen, Bill Porterfield, Mark Gillespie) have the collective key info on these blocks. Each one has graciously helped me on mine. Mark has the records of when built based on unique stampings. I believe he is close to releasing a new book on the yenko Zl-1 engines themselves.

I came away with they are identical to the original 69 casting except for the area of the freeze plugs and foundry, and lack of casting dates. There was a lot of colorful activity on how many were made through Don Yenko (which have traceability to his records) and some that do not. Do not assume all of these came through Don's shop.

[Carleen]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bergy</div><div class="ubbcode-body">This old thread was linked on another site recently &amp; it really brought back memories. We made the cores for these blocks at the Chevrolet Tonawanda Foundry &amp; sent the pattern equipment over to Lockport for aluminum casting. Then the blocks came back to Tonawanda for machining on a special CNC machine that was located up by the doors leading to the main offices. The machine was very advanced at that time &amp; the tolerances were much closer then the regular production equipment. The whole operation had to be quarantined because the aluminum machining chips couldn't get into the regular production chips (aluminum causes pin holes to occur in cast iron). I realize that the ZL-1 option was very expensice, but these blocks cost Chevrolet a fortune to produce! Also, theft was a problem - another whole story! My recollection is that the CNC machine was still in place at least through 1978. </div></div>

Bergy, did Yenko end up whith thise LC Blocks later or was it sold over the counter?