Too easy and 1/3 the cost of a head swap to just replace the engine/ecu/injectors/exhaust than it is to do a head swap because you're probably going to have to rebuild the whole motor to do a head swap. In order to do a head swap, you'd need everything on the top half of the motor, plus an intake, plus a new exhaust system from manifold to tailpoop, a new ECU and the injectors from whatever car the head came from.

I swapped a D15B7, and while it made a huge difference above 4000 RPMs, I didn't change the CX gearbox and it's still a pretty miserable performer. I can downshift to 1st gear at 40mph, but at least I can still get 40 mpg on the highway.