there was a test day for one of these conversions in max power a little while ago, they did it on a MR2, rolling road test with 8 runs, with and without the hairdryer on, the results were poor to say the least!!!!
the hot air caused by the electic motor reduced the performance and at full throttle the motor does not spin fast enough to increase volumetric effiency, although there was about a 1 bhp increase below 2000 rpm throughout the rest of the rev range the figures were under the stock power of the engine, the fan blades were also restricting the flow of the air. out come was that this mod was a total waste of power!
if it is somthing you really want to do then most full kits are about £2500.
Sorry to dampen your fire!!