RC engines work on the same principles as their grown up cousins and will respond to mods in similar fashion. They are mostly air pumps you know.
The trick to porting is just looking at the way fuel and air mixture flow, it doesn't like sharp edges or quick turns and it follows a smooth surface better than a polished surface. Also a polished surface will cause the fuel to become separated due to a loss of surface turbulence that keeps the fuel mixed, this is called "drop out". I have ported and polished from small RC engines to motorcycle engines to big V-8s with excellent results.
make the inexpensive low powered engine make the power you want , that is the essence of what we Americans call "Hot Rodding".