My 127mm CNC alloy housing fan is one of the most powerful around, and cost when converted to USD is very affordable for what you get.
http://www.extremerc.com.au/estore/i...oducts_id=1218
Will run on 12-14s and has been run in the Jet Teng VIPERJET on 14s clocked at over 170mph, in the Jet Teng XXX sports jet on 12s at 170mph.