Last week I installed a crude WAI. Its a double-walled section of 4 inch dryer duct, wrapped in the reflective backing from a piece of duct insulation. It runs from the intake snout to the radiator.
I tried running it back to the exhaust manifold at the rear of the engine, but I didn't have a long enough piece of ducting to get that far.
With the wai running to the radiator, I don't see any intake air heat until the coolant temps reach 195 F and the thermostat opens. This weekend I was driving in 13 degrees F, and my intake air temps stayed at 90 F traveling at 60mph.
http://mirageforum.com/forum/attachm...1&d=1386684108
http://mirageforum.com/forum/attachm...1&d=1386684091
I plan to insulate the rest of the intake snout and airbox when I find more material.