Power = Po x PR x DC x Evol Ratio x PL

Where:
Po is the original rated horsepower: say 240 bhp

Boost + 14.7
PR is the pressure ratio, or ---------------------, at 7 psi this is 1.49
14.7

DC is the density correction due to heating of the air charge. This is directly
proportional to the absolute temperature of the ambient air to the boost air
entering the engine. At 7 psi these corrections are about .85 without an
intercooler, and about .96 with the IC.

Evol is the volumetric efficiency ratio of the blower to the engine. Since the
CS and the turbo have the same Vol Eff, and the engine is the same, this factor
can drop out.

PL is the power loss correction due to the necessary power taken from the
crankshaft to drive the blower. Here the CS takes about 5% of the engine power,
whereas the turbo only robs about 1.5%. The reason for the difference is that
the turbo is largely powered by the heat energy in the exhaust gas. Keep in mind
that the heat energy lost out the tailpipe is about the same number of horses as
the engine makes. Remember, of the fuel burned, 1/3 goes to power, 1/3 to heat
in the cooling system, and 1/3 out the exhaust. Therefore the lost exhaust
energy and the engine power are about the same. When was the last time you saw a
240 hp fan? That is what is made available to the turbo for a driving force
without taping off the crank. We don't need it all, but that's what's
theoretically available. Enormous, eh?

Intercooled Turbo:
(7(psi)+14.7) = 1.49
P = 160 x 1.47 x .96 x (1 - .015) =

222.4whp @ 7psi