How much power will it make?

Port injection is a big improvement - but requires the injector bungs be installed or a specific produced manifold. But - carbs do an adequate job of mixing fuel and air. Fuel injection does a much better job anb is much more precise. Plus, injiection adjsuts itself constantly at the speed of light. So things like jetting and power enrichment are all handled much more efficiently. The end result is more torque, usually more power, easier starting, better idle, cleaner plugs, less fuel conatmination of the oil... It's just better all around...lol.