You need the one sold specifically for supercharger use-the poppet type do not flow enough to be useful in a compressor bypass valve.

The one from the Mini Cooper S would work just fine:

http://www.ebay.com/itm/Mini-Cooper-...-/191986610258
http://www.ebay.com/itm/2002-2006-Mi...-/262896611747

You might look at the stock eaton blowers on Ford and GM stuff for your ideas on where and how to plumb it.