Sorry if this is stupid...but what is grill block?

It's quite simple, actually.

Some people used foam insulation normally used to wrap around tiny water pipes, and push this into their grill to block air from rushing through the grill and thus cooling off the engine.

This is because the cold winter air cools down the engine much more than the engine needs to run comfortably, and in effect, the engine needs to run more to keep it's heat and be able to keep the cabin temperature at desired levels.

This has been done for ages in colder climates (like here in Norway). Many people use pieces of carboard or such to block for instance half the radiator to make the engine run a little warmer. The engine gets warm a lot quicker and retains it's heat for longer times. As the Prius shuts off the engine as often as i can, this is a bigger issue for the Prius than most other cars.


-Stein

 

This thread has some nice pictures showing this:
http://priuschat.com/My-attempt-at-grill-b...ing-t39790.html

 

<div class='quotetop'>QUOTE(skanDALE @ Oct 23 2007, 03:21 AM) [snapback]529190[/snapback]</div>

Wow! Those are some really nice photos!

 

<div class='quotetop'>QUOTE(Green Hokie @ Oct 23 2007, 06:58 PM) [snapback]529335[/snapback]</div>

I only link to the best!