Nick's Garage dyno's a 318 Stroker.

Yup, the blocks are purt near the same. It can be argued though that the Poly heads are better than the LA heads. At least that's always been my opinion. Chrysler ended production on the Poly for the same reason as the Hemi. Cost. They were good power makers.
They were a great head design. Too bad they were so big. They wouldn't fit easily under the hood of the newly designed (smaller) 63 A Bodies.