both maxed out, on stock internals, easy win for the Terminator. If both are on pump gas, easy win for the 5.0.. (higher compression makes for more power in the 5.0, MUCH better internals in the Terminator make for more total power)
Not quite sure I follow- a motor's not going to make more power just because the pistons and rods are forged. There have been plenty of stock block Coyotes on various power adders in the 800-900rw range. Sure, they won't hold it for long before the rods go poof, but they can do it a few times.
Pulley for pulley on the same charger the 5.0 wins due to higher CR, tivct and better flowing heads. The stock manifolds don't really cork it up much either.