Please explain HOW to block the grill

Any of the above will do. It just depends on the look & convenience you want.

For me, squeeze & push is all I do. Each slot gets a full piece of pipe insulation. See...

more & bigger photos here


Others choose to span 2 slots with a single piece of pipe insulation. With that technique, you need to fasten it too. But some prefer that look and no squeezing is required.
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Forgive my newness to the forum, but what does this grill blocking do for the car?

 

Not much, for you. Had your location been Winnipeg, we would have serious advice for you!

http://www.wunderground.com/cgi-bin/findweather/getForecast?query=goodyear az&wuSelect=WEATHER

 

Get either 1/2" pipe foam (2 pieces), or 1" (1 piece), with no adhesive. If you get the 1" stuff, split it in half lengthwise.

Cut to length (around 29" for the bottom openings - the leftovers can be used for the top).
Push one edge of the foam into the grill hard enough to create dents (in the foam, not the grill) where the vertical fins are. Use that to determine where to cut 1/2" slits.
Then just squish the foam flat (with the 1" stuff, you have to fold it) and slide/stuff it in. Trim the ends as needed.

 

The picture shows what I done. I used 2m of 26mm (1") insulation tube. Cutted it lengthwise to make an opening for the insert. Cutted two long pieces (upper and lower portion), marked the place where vertical bar were and cutted to the 1/2-3/4 of diameter at marked positions and inserted. From the rest of tube I cutted smaller pieces for the center inserts. The grill block survived auto carwash w/o problem. 15 mins work all together.
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That is the identical thing that I did to my Prius.
And you are right, it holds up in this cold weather and through car washes.

 

On the 2010 the lower grill looks like the Gen2 but the open area is quite a bit shorter (probably a couple inches or so). I'm using the full length tube from the 2006 so the twist ties are really holding them in place. Based on Barbara's experience I absolutely recommend ties on the lower grill block.

On the 2006 using the compression fit technique on the upper grill I lost 4 of the 8 pieces over the years.

 

Were you using 1/2" foam squished into a single slot? I've never lost any that way. In fact, you have to tear it out in the spring.

Perhaps there are different kinds of foam, some with better grip (rougher surface) than others.
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I used black zip ties to hold mine in. Next year I will do something nicer looking for sure.

 

Nice thing is, they're very cheap. You can always try again if they don't hold or if you just feel like making it right to your satisfaction.
Keep in mind that you may need to adjust the amount of blocking with the weather changes. We had temps in the 20s a month ago and just over 60 the other day.

- D

 

I used 1 1/8" IDX 1/2" WALL R3.1 25/50 FM (in a diamond) 091953 in the upper grill. Those spaces are 3.1 inches on the ends & 3.3 inches long in the center & much narrower compared to the Gen 2. I used a printers rule & measured in pica (10 pica=1 inch). With a scissors I cut a 3.1" length & fit it over the grill. If the pieces are cut short there will be a bit of space. If they are cut a bit wide the foam will compress & fill the space nicely.

 

Here's the finished look. The edges of the VentureShield film can be seen around the grill.

 

Nice job!
Did you do 2 rows of insulation on the bottom grille?
I did 3 rows of 3/8" insulation.

 

Thank you. I'm happier with the top than the bottom. Yes, the bottom is composed of 2 tubes. They sit on top of the grill because they are longer than the opening and I never bothered trying to cut notches for a better fit. If they aren't tied down they will fall off. On the Gen 2 they fit the opening & were tied down "just in case".

 

I'm late to this game (just put mine in for the 1st time ever a little while ago), but I'm like you John -- I don't see how mine would fall out. In fact, after they were in for a week, I couldn't easily remove them without tearing them.

I use less foam than anyone else I've seen reported here. Not only do I use 3/8" Frost King pipe insulation (the round tubes with a slit), but I cut them in half along the length.

On my Gen II, I use only 6 pieces -- 1 continuous piece for each slot.

For the 2 top slots, I cut the 36" length to fit.

For the 4 bottom slots, I keep the full 36" length of the foam and tuck the ends in behind the panels where the foglights would be if I had foglights. This creates a grille that's similar to the Honda Insight's top grille.

I didn't bother cutting slits or notches in the back to accommodate the vertical fins (but I might try that next winter).

Here are some pics:

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[IMGLINK]http://priuschat.com/forums/attachments/gen-iii-2010-prius-main-forum/20888d1262724484-what-did-you-do-your-prius-today-002.jpg[/IMGLINK]

 

Great job Tom, looks great.