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Looks like a 4v head with the larger intake chambers. Just a thought.....
 

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^^^ I tend to agree.

First the head appears aluminum and there were no factory Clevelands with aluminum heads in the U.S.

Next is that screw-in core plug on the end of the head which is definitely NOT U.S. production.

One thing counting against the Yates I.D. is the canted valve arrangement. IIRC the early ones were canted but this was taken out for NASCAR-usage durabilty. Later model Yates heads had an inline valvetrain so rocker shafts could be used. I've heard that that is no longer a concern and the engine builders would like to go back to a canted valve set-up but the rules do not allow for it to happen.
 

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Aluminum canted valve Cleveland-looking heads show up at All Ford Columbus every year that look like the ones in the photo. Since they were usually in piles with the Nascar intakes I asumed they were Yates heads.

I thought Yates heads were for Windsor blocks though. The pictured block is a Cleveland.
 

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Head ID

These are the SVO high port heads that came out in the mid '80's. Youwill notice that the valve cover is also special. It was introduced in the same era to combat valve train instability at high RPM.

The head is all aluminum, US made of course, M-6049-A3
These heads were designed as the first true bolt-on Alum head for iron headed cleveland motors. However the exhaust port was raised, imagine, and it would not bolt on to us "street" guys' motors.
The intake flowed around 295 at 0.700" with 28" H2O depression
The exhaust flowed around 200 at 0.700. You can see this is enviable even today -- although a porting job would make them better. And these heads sold around $600 ea/bare!

The valve cover p/n is M-6582-A351 which sold for around $275 new.
 

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Yup. Looks like a 80's SVO HEAD, I recognize the acorn nut on the cover from the old catalog, i still have it somewhere
 
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