[olddog]

From what I have studied (no first hand experience) any type of forced induction has the problem of heating the air. The less efficient the blower the more waste heat added. On top of this waste heat, anytime you compress a gas you increase the temp. This is why you will see after-coolers to bring the air temp down before it enters the intake.

If you run at mild boost level say 5 psi, you can get by without the after-cooler, as long as you do not have too much compression. Air at 70 deg at sea level is at about 14.7 psi (I'll round to 15 psi). So 5 psi boost is about a 33% increase in air density. So, your engine would gain about 33% more HP minus the HP used to drive the blower. This is an ideal case that you will not likely achieve. Also since you increased the density of the air by 1/3, you have affectively increased the compression ratio of you engine by 1/3. So, a 9:1 compression engine would act like a 12:1, as far as the air temp in the combustion chamber at TDC on the compression stroke. Therefore, you have to pay attention to the compression ratio and the air temp exiting the blower, or you can get into pre-detonation quickly.

At high boost levels intake valves can actually be pushed open. So, going high on the boost gets more and more technical.

Multi point EFI is much better suited to superchargers, but carbs can be used.