The stock ECU runs really rich to ensure long life and reliability. Cars make more power running lean than rich so the Camcom tunes it lean. However, running lean can be very very bad for your motor if taken too far.

I dont know what to say....
But, stock ecu doesnt run really rich, because its bad for fuel economy, it will burn out the car quite early. Cars dont make power running lean, they make power running slightly rich, but thats not all, you need to have more air going into the engine and more fuel, thats why if you want power, you're gonna lose fuel economy.
Lets say you have one teaspoon of gas and air mixture (hypothetically), you wont get any more power by having more fuel than air in that teaspoon or vice versa, you need to add another teaspoon of the same mixture to get power.
However the engine can only suck a certain amount of that juice into it, per induction stroke, and no amount of intake installing/exhaust installing will help, because the head and the ports in the cylinder cant flow more air/fuel mix, that is the main bottleneck on most engines. Not to mention the stock valveshape and angles are bullshit, which dont certainly help peformance, but they are a compromise setup.
Thats why you want to enlarge the intake ports, and have a 3 angle valvejob and oversized valves done on a NA engine, combine that with some nice high lift- long duration cams and you can really go, but emissions and fuel consumption WILL increase, becuse at low rpm the large ports will cause the air speed to slow down and fuel will drop out and puddle in the intake manifold/intake runners.
Flowbench testing indicate that even a D16 head will flow better than a stock 4A-GE head, kinda scary huh? I gotta hand it, I think hondas suck, but those guys _DO_ know how to make engines flow air. They dont make much torque, but they do flow a high RPM relatively better than toyotas counterparts.
Heres a graph that shows that power is made on the rich side of the stoichiometric graph and fuel consumption at the other end, the stock ecu will try its best to maintain a stoichiometic fuel mixture in all except wot conditions, so fuel consumption is reduced.