GP wrote:Checked the temp under the bonnet and found that there is very little difference wherever it's measured which is what I expected. I also checked the temp in front of the windscreen where a lot of people draw air from and found that it's no cooler under speeds of about 80kph.
If you want cool air I suggest it needs to be drawn from the front somewhere. (This is my NA of course)
Well done I came up with the same conclusion!

The major air flow into the engine bay is thru the radiator hence the air will be heated to approx 80degC, there is no getting around this fact. I have done extensive temperature measurements on my NA and found you must find a fresh (high pressure) feed for the air to your intake to gain any power improvement. If you have forced induction you can rely on your intercooler to remove the heat so intake temperature in a mute point.
I have ceramic coated headers yet some of the articles I have read tell you that you need an (expensive

) heat shield to protect your supercharger from all the heat radiated from the headers, I have found that this is not the case. EVERYTHING under the hood runs at 70-80degC when your moving, all cars heat up under the hood when stationary as the only air flow is from the cooling fan.
Ted