Under the bonnet is August but in the Sahara at mid day!
A while back I did some crude measuring of air temps.
OBD unit measured incoming air temp, 15deg ambient and OBD reading 35deg and still rising.
The surface of the polished filter box was reading 50deg on the surface with a thermometer.
The “ rule of thumb” is 1bhp extra for every 7deg lowering of air temperature.
I might actually get on with further attempts to get cooler air. I have taken the bonnet extenders off for the winter though.
