76 GP engine

I'm new to the Forum.....so Hi to everyone.
My newly aquired GP has a 400 CI engine. I want a stronger power plant. My question is would it be cheaper/easier to build up the 400 or to do a motor swap? Any advice at all will be greatly appreciated.
I'm sure I'll be needing lots of assistance with this as I'm not that familiar with Pontiacs yet.

Thanks, MW

Build up the motor you have now, as long as it isn't too tired. A simple manifold/carb swap and a cam will really liven up that engine. Don't go with headers unless you're gonna run it hi rpm. On a torque motor, headers are not worth the hassle.