About 20 years ago I data logged all these sorts of question through my Autronic ECU in the first gen RX7, I was running a S5 motor with a 20B intercooler up front, I tested all kinds of things, and found out what my mate with the outrageous signature size is saying!
I still have the logs and software to see them, I need to take pics and post them up. I increased the efficiency of the intercooler a metric arse load by encasing it in a really sic scoop that hung out the front of the car, ( I have a track photo from 1994 showing the scoop!) this brought down the IC charge temp by over 20 deg C, the theory was the mass flow of air at pressure was being forced through the IC and not over and around it..... math is simple basic mass flow of air is acting to transfer heat from the IC core, higher flow rate of air and greater density = far greater heat exchange between the two.
TO give you an idea I went from 70 deg C charge temp to under 50 deg C (despite running more boost! and running in ambient conditions that were 15 deg C hotter!) at 240kmh in the top of 4th gear.
The stock top mount IC's can work good but you need a good hood scoop and a sealed bonnet at minimum. A water spray system helps no end as well cause at power levels over 400bhp (engine power) the charge temp will always be too hot as its just too small when air is the cooling medium. If you encase it in a water jacket then its a different story
but that is a whole nother question and level of complexity.
