Close Chamber or Open Chamber Heads?

Most guys buy the closed chambered heads and then adjust the head gasket thickness to get the proper "piston to head" clearance. Stock early 340's tend to have pistons protruding somewhat above the deck, but you really have to measure it after all the machining is done at mock up.

As far as power from your "paper" combo.......A solid 400hp would satisfy me.......As long as you're willing to gear it right & use the proper torque converter?