For the second part of the test (part one is here) I reattached the accordion to the airbox so that cold air would be directed into the intake.

I made two drives, a morning and afternoon drive.  The morning was the same route as I have taken before, the afternoon drive was shorter due to taking an alternate route that put me on a highway for a short distance rather than sitting in stop and go traffic.

The drives with the ‘cold’ air intake are shown in pink and bright green.

The results from these drives are inconclusive, which leads me to believe that the differences are negligible.

Efforts to build a ‘cold air intake’ or worrying about having a ‘hot air intake’ are probably wasted energy.  With the warming that the turbochargers cause to the intake air, even when not in boost, and the cooling effects that the intercoolers offer, these producers of temperature change are much more significant to the temperature of the intake air than where the air is drawn in from.

Some will argue that ‘every little bit counts’, but in looking at the chart above I don’t see where the cold air setup provided any distinct advantage over the hot air setup.