Thanks for the info Earlie-A.
Yep Poly heads are rarer then early hemi heads.
The intake port has very similar dimensions to a hemi head.
The exhaust is the downfall like any head from that era.
If you look a 276/291 Desoto head its scary how tight they are!
But now we know that the Hinkles Poly worked it out and made 600hp.
Just imagine how much more it would have made with an LSX Domi manifold?:BangHead:
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