If you put a blower on a stock motor, it still makes more power, right? Even though you didn't increase the size of the exhaust lobe. How can you get more in if you didn't get more out? The answer is simple... since you had more cylinder pressure, the greater pressure difference across the exhaust port allowed more exhaust to flow through the port, even without more cam or port. To optimize this requires only a small change in the exhaust side of the motor to match the boost levels you are using. Since these engines are too heavily exhaust biased to begin with, my recommendations for a blower cam come out looking like straight pattern cams.

When you pressurize the intake to two atmospheres, the column of air in the runner now has twice the density; therefore it has twice the mass. This means it is actually harder to accelerate it toward the cylinder. Proper exhaust scavenge during overlap is still beneficial filling the cylinder, even with forced induction. The motor still needs adequate overlap to fill the cylinder effectively.