Cars with factory fitted grille blocks
 

I noticed my 320d -08 has factory installed automatic grille blocks that works similar to window blinds. Never seen them open but I would expect the weather to be pretty hot before that happens.

https://t2.gstatic.com/images?q=tbn:A...WIRr7m_U-tfISQ

It also has a pretty flat and smooth under body floor so no need to make panels there.

What other cars have this already built in by design?

Shows you don't have to be nuts to do something like this because at first glance you don't see it. That means they must have done these things because they really think they work.

Re: Cars with factory fitted grille blocks
 

I know the Chevy Cruze Eco has a similar feature. A couple other models do, but I forget which ones right now.

Re: Cars with factory fitted grille blocks
 

The new Focus has it. Might only be on the SPE (their ECO).

The Ford C-Max Energi has them too.

Most new cars have these, my Clio does too. They are not only for heat purposes, in my case, they shut at certain speeds to restrict airflow into the engine bay and make the car more aerodynamic.

Corollas had these in the 80s :)