so you have tryed opening your bonnet at 50 mph to feel the rush of cold air coming in through the grill
Everyone who as ever driven around with their fresh air vent open or heater on would have some idea.
Similarly if you've ever been to a rolling road, or driven up a really steep hill, and noticed the how hot things get without the usual cooling effects of airflow when driving at road speed you'll have an appreciation of how effective a bit of a draft through the front grill is.
Bet we can keep this running for another week 'n still be no nearer a definitive answer.
Well my mini has the two fresh air vents hosed up differently. The drivers side is ducted via standard vent hosing from the grill whereas the passenger side isn't, it just draws air from the engine bay. The drivers side is understandably cold while the passenger side spits out warm/hot air depending on engine temperature.
Explain that one?