[aerohead]

If I understand the premise of the modification correctly, we're talking about boosting the ambient air entering the 'suction' side of the turbo to above atmospheric pressure, with an electric turbine.
If this is correct, then I'd have the following comments:
1) The OEM design already provides for cold-air intake.
2) Since the turbo already provides artificially-enhanced induction, 'ram-air' wouldn't necessarily improve the situation, and might cause harm.
3) The OEM turbo setup is already capable of delivering more charge than the engine is capable of ingesting, even at very high elevation ( Pike's Peak ).
4) Impellor boost pressure available to the cylinders is constrained by the waste-gate on the turbine end of the shaft.
5) Without boost pressure control, combustion pressures could exceed what the engine can tolerate without damage.
6) Arbitrarily boosting pressure on top of the impellor circumvents the waste-gate's protection, allowing enough charge to turn the engine into a grenade.
7) Blowing up the engine is not efficient.
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If you really want to increase the vehicle's efficiency, consider reducing it's LOAD, via lower rolling-resistance, and lower aerodynamic drag.
Leaving the engine alone will maintain it's durability and reliability.