Smallblock Heads?

Which heads are best? Well, none out of the box that's for sure, though, I think Indy heads would do it in a OOTB condition or close actually. Alot is engine combo dependent.

Brodix also has a real nice set of heads. Similar to the W-5. The moved centerline heads have a 2.15 intake valve and IIRC an unresetricted cross sectional area like the W-2 or W-5 as well.

Some work to each head would let the 4inch stroker sing well.