<VV> Jetting on (part 2)

[aeroned at aol.com]

OK, now that I've been educated on jets and mixture, I have another question. Without using a dyno, air/fuel meter, O2 sensor or any other instrumentation how would a person determine the proper size jets for the engine?
 
Lets say for the sake of argument that the engine is a Corvair 140 0.030 over, OT-20 cam and "Extractor" exhausts.
 
The stock jets for 140 primaries are 0.051. I've heard some here say that 0.053 really increase the power.
 
Ned