[Dozer42]

Anyone tried it?

I was searching the Prius forums for real world examples of switching from stock wheels to lightweight wheels, and one person mentioned he got a larger increase in MPG from Grille Blocking than wheel size/weight.

Has anyone looked into this or considered it with the CT200h?

Here's a link to the thread: How much do you block your grille? - PriusChat Forums

 

[lexceetee]

Ehhhh I think i'm aerodynamic enough as it is. I just looked through the provided link and quickly noted the risk of potential overheating which was the first thing that crossed my mind at the mention of this. I don't think the MPG increase would be signficant enough, in my case at least, to go through with this.

 

[Lexusito_de_mi_vida]

Hello. I did it.

I owned a 3Gen prius and traded it for a ct200h. In prius, grill blocking worked. I also blocked the radiator with a foam pad. Got a -0.10, 0-15 l/100 km fuel consumption.

Now with the ct200h i only blocked the lower grill. I plan to put the foam pad in front of the radiator as well. But i will wait for colder weather to do so.

You shouldn't be worried about overheating unless you drive fast or on very hilly roads.

 

[Wass]

I blocked the lower grille last winter and saw approximately 2.5% better fuel consumption which may have been due to a noticably faster warm up time on those cold winter mornings. I found that the car would run happily with the lower grille blocked in ambient temperatures up to 15 degrees C

 

[Lexusito_de_mi_vida]

If temperature is up to 25ºC block grilling is not needed.

But if temperature is less than 25ºC I'd recommended it. Specially while driving, cold air enters inside the hood and engine gets cold. Grille blocking tries to avoid this from happening.

88ºC to 92 ºC is a good margin to keep the engine coolant in. Those who own an scangauge can monitor the value. I do it.


What we shouldn't do is to block the upper grill. This one directs the air to inverter cooler, whose temp the lower the better.

 

[Bigleftyinaz]

Anyone have pics to share how you did this mod?Been thinking about doing this now colder temps are coming again.

 

[Lexusito_de_mi_vida]

Anyone have pics to share how you did this mod?Been thinking about doing this now colder temps are coming again.

The mod has two parts:

- Block the grill.
- Block the cooler.

You can block one or both of them.

These are some pics from my previous car, the 3Gen prius. You won't need to take out the bumper in the ct200h if you want to block the cooler. There is more room than in prius once you removed the plastic cover.

The material I used to block:

Grill blocking has no mystery:

In my new ct200h I blocked cooler about 70% of its surface. And I blocked grill 2/3. When weather be colder I will block more.

In my first days driving the car, I am founding out ct200h to be hotter than prius. I mean, ct hood is better thermal isolated. Maybe lexus stuff read the forums...

 

[Suzukonakai]

anyone can explain why need grille block? ... sorry I'm not a car person....

 

[Lexusito_de_mi_vida]

anyone can explain why need grille block? ... sorry I'm not a car person....

Hello. Probably you noticed that summer consumption is better than winter one. For various reasons.

Grille blocking tries to simulate summer conditions by avoiding over cooling due to lower winter temperatures. It will never be as good as real summer temperatures, although you will get a little fuel consumption improvement.

Other advantage would be that it is a really cheap mod.