427 yenko all aluminum block

[wazntme67]

Hey everyone. I am new to this forum and have come here seeking more information about the yenko all aluminum blocks that were built back in the 60s and 70s. I recently purchased a block that has yenko on it and is supposed to be an all aluminum block. It only has 4 letters on it "SYHE", and says yenko on it. Does anybody know what these letters might stand for or have any other information that would be useful?

[jannes_z-28]

A picture would help.

[iluv69s]

Yenko started making the blocks after 69 and they apparently made various versions. Some being tall deck for larger stroke/ cubic inch options. There are some past threads on the subject here if you do a search. The SYHE is commonly stamped in the timing chain area. I have many fotos of different types/configurations on the ZL-1/Yenko alum. blocks. Some had push-in freeze plugs and some screw-in. Some had Winters foundry logo..others had different founndry..there were various different YENKO letters and/or insignias. If you PM me, I can see if any seem to match your block.

[wazntme67]

I hope these pictures come up, but here are a few I took today. I really appreciate the information and desire to help. I tried looking through the threads, but came up empty.

[wazntme67]

s

sorry the pictures turned out upside down.

[markus37]

I have the records on the Yenko ZL 1 program. Send me a message with your email.