I've picked an entire P7 top end (machined heads w/ titanium valves, ported manifold, TD rockers and stands, valve covers etc..) in anticipation of the XR block, and I grabbed a pair of P7 bare castings and intake off EBAY, so I'm glad to hear you say one could start from scratch on the P7 heads and have them done specifically for drag racing.

P7 Stuff is super cheap right now. The bare heads were 180.00 shipped!