I recently bought a 1966 Coupe De Ville. Everything I've found has showed that I have a 472, not the 429 (valve covers, front assembly differences, ect.). My question is, what is the little tube looking thing between the heads? Goes from one head to the other, has a little filter looking thing on it. This is my first Cadillac engine and its got me stumped. Thanks in advance!

 

It sounds like it maybe an AIR tube

 

Thanks! Its the blue tube in this picture. I couldn't get it to upload in the original post.

 

AIR tube

 

Awesome! Thanks again.

 

The picture doesn't show it very well, but that appears to have an HEI distributor.

Someone put a much-newer engine in the '66 body. You've probably got a matching "newer" transmission to go with the incorrect engine.

Perhaps I'm not seeing the distributor properly.