EBAY stuff is JUNK.
E-RAM
http://www.electricsupercharger.com/ See MARK KILBORT 928 RACER from RENNLIST. Proven time and time again to work.
ESC-350 or 500
http://www.turbomagazine.com/tech/0406tur_knight_turbo_electric_supercharger/ Proven to work.
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