Originally Posted by
Karlos G
When a car is designed the cooling system and air flow characteristics of the engine bay are all modelled/tested with the bonnet fully closed... Raising the back ruins all of this and can result in higher temps or at best the same.
It COULD also allow the air out the back of the bonnet and aid cooling. I can certainly see hot air (waves) at the rear of my bonnet so I know heat is getting out and my car doesn't overheat like it used to but that was more down to the header design that has now changed.
It all depends on the application. Car manufacturers have the ability to amend the design at that stage until it works, a manufacturer is unlikely to resort to lifting the back of a bonnet. Just because they work to their model it doesn't mean it wouldn't work but I can also see that it MAY cause issues on some cars.
The abarth 500 had the boot open the whole time for cooling and some 911's had different "boot" lid arrangements for aero and cooling.