Bonnet raisers - Not everyone's cup of tea

[cwspellowe]

As Chris said, they don't aid cooling when driving as the base of the bonnet is a high pressure area , higher in fact than inside the engine bay. As air moves from areas of high pressure to low pressure, this actually inhibits cooling to the rear of the engine bay.

So on a 306 it's purely being done for looks, and they look ghey.

Case closed.