I finally got around to installing heat shielding on the underside of the engine cover to stop heat soak. The heat shield I used stops 90% of radiant heat from getting through so keeps my engine cover/airbox much cooler. I noticed a difference straight away when driving to work yesterday as my mpg quickly went up more than usual. I have not got Vagcom etc so I cannot measure the difference in temps. However after a good 25 mile drive the engine cover top was only very mildly warm and I could easily reach round the back near to the OE heat shield above the manifold and touch the engine cover with out burnng my fingers. A good little mod this as the OE airbox must suffer from heat soak with all that hot air rising from the engine and exhaust manifold/turbo etc.

can some pics up

How does it work?,What does it do?

How does it work?,What does it do?

Just helps prevent excess hot air from around the engine getting to the rest of the engine bay.

I'd be slightly concerned about focussing/trapping the hot air around the cylinder head though.

Never heard of anyone doing this, does it really need to be done? Not sure I'd want to be heating up the coil packs :wonder:

It will make a difference and as I work for a company who supply heat shield solutions we have things like this pop up once in a while for the car industry i.e Subaru Cosworth is a fairly recent job we work on to keep things cool in the engine bay. http://www.rbfindustries.co.uk/fibre-tech/applications.php

I will post some pics up when I take the engine cover off again.

The hot air is not trapped between the cylinder head and the engine cover as there is a gap between the two. Once driving it gets a natural flow of air going through however after time the heat from the engine builds up and heats up the underside of the engine cover(heat soak). Since fitting the heat shielding it keeps the engine cover cooler to touch which means the air box is also cooler and the iar inside the air box is cooler before going through the turbocharger. The air does get heated up by the turbocharger granted, but cooler air is more dense and is cooled by the intercooler more efficiently.

Should make it warm up a good deal quicker in winter too if it's holding back as much heat as you're suggesting.