I dont know if this would be of interest to other turbo builders but i was a bit concerned about getting cold air to the intercooler and oil cooler at low forward speeds also the heat being pushed out just under the back cover.
this in line boat bilge fan looks just the job as you can connect a 3" duct in line. I have got one on the way but it has not arrived yet.
http://stores.ebay.co.uk/12V-MARINE_...dZ2QQpZ2QQtZkm
all the best
tony