anyone hear of a h-p big block sawtooth 318?

I agree, sounds like a Poly.
Since the 318 Poly was essentially the same block as a 392 Hemi, I would call it a big block too. It is certainly bigger than a LA 318. Quite possibly I have just proved that , I don't have to be a Chebbie guy to be an idiot:sad5:
Someone help us out here?

No no no, the frezze out plug mention is the "BIG IT" on the poly 318.

(Polys don't use flatop pistons) you would be hard pressed to tell the difference. In fact, late heads nearly fit. Many parts including the timing cover (I believe) and pan will fit.

IF I could only download my camera pictures of the poly I just got, I'd show ya flat top slugs.