i just took a look at the grill and radiator, and i noticed that inside, the grill is blocked except for around the radiator. the block isn't flush with the grill but straight up and down around the radiator.
lol, how about an illustrated photo? i couldn't get a decent photo, my camera is crud and there is very little space under uncle yaris's hood.
the yellow blobs represent the two grills on the front, the green lines represent the radiator, and the pink lines represent the block around the radiator
it isn't flush with the grill, so there is probably 6 inches of space in front of the radiator/block that tapers up to the top of the radiator.
You start blocking the grill in the summer time and you will loose AC and the fan will run a lot more and you will end up overheating the engine. It usually runs around 182-186 F with traffic and the fan kick in at 195-205 F - you get less engine wear at the lower temperature according to Miro at Synlube - I asked if higher temp is better and he said that they richen the mixture to help cool the engine when it gets too hot - plus the fan draws a lot of battery power when it kicks in. I would leave it alone until you get it broken in more and the temps gets cooler - winter time is when you really need it to make more heat for the cabin heater. You would think they could color match the hubcaps a little better for the car - that's why I painted mine white.