Upper Grille Blocker & Intercooler screen

[RichieRocket]

I wanted to block the lower grille for the winter season, but I noticed the intercooler was across the bottom. So I blocked the upper grille instead. Hopefully that will improve the airflow around the nose and improve mpg

I'm wondering if the intercooler is getting good air flow being set down so low. (I'll start a new thread in 1.4T forum)

I used some old plastic house siding sheet that I had to block off the upper grill. I cut it to fit and painted it with flat black. It is held on by cable ties (zip ties). Up close it looks hack with the cable ties, but it'll do the job.

On the bottom I want to protect the condenser and intercooler from sand/pebble/rock damage, I purchased a sheet of gutter screen with 2/10" holes at Home Depot. Now I need to decide what to do with the license plate location...leave it as is or move it up by 3-4", that would block the chevy logo.

Don't know for sure, but it seems like the towns are cheaping out on the road sand they use and are not sifting out the pebbles like they used to...

 

[Eric Smit]

What a brilliant idea; the gutter sheet over the intercooler.

 

[LS1notFOUND]

neat idea, I wonder how much flow through and out the engine bay it does w/o blocking. I personally wouldn't do it because in the event of heat related warranty claim it might be an issue.

As far as license plate go, could attach it off the side like some EVO owners do, or even have that inside the grill like I know some hot rod guys do and help with your blocking off

 

[RichieRocket]

neat idea, I wonder how much flow through and out the engine bay it does w/o blocking. I personally wouldn't do it because in the event of heat related warranty claim it might be an issue.

As far as license plate go, could attach it off the side like some EVO owners do, or even have that inside the grill like I know some hot rod guys do and help with your blocking off

LS1notFOUND, not sure I understand what you mean by heat related warranty claim? I am only blocking off the upper grille for the winter. Since I live in the northeast, the temps will be low for the next few months, so why have the AC condensor and intercooler exposed to sand/pebbles damage and why not cut down on some aero drag like the Chevy Cruze does for better mpg
The cooling system is designed so you can drive in AZ in summer, so driving in 30F temps, you don't need full cooling capacity

For the license plate, I did look at the side areas, but it didn't look like there was any good places to put it...I'll probably leave it where it is for now...

The mesh in the lower grille will hopefully keep out (or slow down) most of pebbles trying to get in.

I was shocked a few years back looking at my car's radiator, the radiator in the area directly behind the lower grille openings, had all the fins bent over so barely any air could flow thru. There are actually fine tooth 'combs' made to straighten radiator fins like these
That's what I'm trying to prevent.

 

[Danny5]

TTIWWOP!!!

Seriously, post up your hack job!

 

[RichieRocket]

Pic of hack job... not a good pic, too much contrast with the reflection from the license plate

I made it from two overlapping pieces, held on by three black cable ties, painted flat black. You can see one of the cable ties in the pic...

 

[mike]

have you noticed any change in fuel economy with the grill blocked?

 

[RichieRocket]

have you noticed any change in fuel economy with the grill blocked?

Can't really say for sure, have not had an opportunity to do a back-to-back test. Chevy claims the Cruze ECO reduces drag by 5% with the louvers closed-down. BUT the ECO closes the lower grille, so it's not an exact comparison.

Two minor things on the blocker are improving warm-up time and protecting the A/C condensor and intercooler fins from sand/pebble damage. ( in GA, that's not really a concern for you)

Assuming I did get a 5% aero drag reduction, the real average fuel economy improvement would be small, probably 1~2%, very hard to accurately measure.
- The aero improvement would mostly show up at highway speed, 1/2 of my driving is non-highway.
- At 70 mph, the total drag is roughly 60% aero and 40% friction (driveline, accessories, tires, etc), so that 5% reduction is only working on 60% of the total drag.

Too many variables between fuel-ups to see anything in the fuelly average tank mpg (see Fuelly below). I could do a back to back where I drive a highway loop with and without the blocker, set the cruise on the first run, do not shut the engine off while removing the blocker so the cruise 'resume' button can be used to get the exact same speed on the second run.
If the 5% was real, it would be a 1 ~ 1.25 mpg increase.

You have inspired me to try that out, I'll try to get it done today, depending on what my wife has already planned for me today...

 

[mike]

glad to hear your warmup times are better with it blocked. i am moving to around Albany next year most likely so i will definitely try this mod out then.

 

[RichieRocket]

OK, so I got some real data, I had to wait until after 10:00, so the traffic would die down.

Engine fully warmed ~220F, outside temp 20F, I set the cruise control at 75mph and never shut off the car so I could just hit resume and it would go to the same speed for each of the 4 runs.

I don't have any flat stretches around me, so I used a hilly section of I-91 north of Hartford. The loop was 13 miles up and 13 return. To be consistent, I got up to speed and reset the average mpg as I passed the same sign and noted the average mpg at the same end sign post each time.

Unfortunately the wind is gusty tonight, it was blowing the car around on the bridge. That had to have an effect on the result.

With Upper Grille Blocker out: 32.2 return: 34.1 average: 33.2

No Blocker out: 31.4 return: 33.8 average: 32.6


So the blocker improved the mileage by 1.8% That is with a lot of uncertainty on the data above, so it is a preliminary number....more tests would be needed in better conditions.

 

[Ferdie]

Huh i don't understand why you block the upper!

In the upper blows the cold wind into you're engine buy! the cold air is then cold and on the end of you engine buy is it hot then it leaves your engine!


the other is for cooling you're intercooler behind it is also cold air! and the upper blows the cold air so to you're hot engine that the under cold is!

 

[Danny5]

Ferdie, isn't it blue balls cold where you are right now? Lakes frozen over and stuff?

Blocking off airflow to the radiators is a common practice where the temperature are consistently cold for extended periods of time. Its not uncommon to see entire grills blocked off during the winter time in the far north.

 

[Ferdie]

Hmm it is here now cold but not that cold!

But now i'm getting the point when it's verry cold! sorry my bad!

we have here now 8 days frozen whetter but not thad cold!

every day you learn something

 

[RichieRocket]

Ferdie, if you think about it, the cooling system has to be designed to not over heat in AZ during summer heat 120F (45C) under heavy load. In the winter, all you really need is an intake of maybe 3"x3" (8cm x 8cm) to get enough cold cooling air and that will help aerodynamics.

There are many ecomodder sites which have people doing that. They make a grille blocker with a sliding door that they can control from inside the car. They install a LED light on the dash to tell them when the radiator fan is working. If it's coming on very often, they slide the grille opening door larger to let in more air. That way they always have just enough cooling air flow.

I'd like to cover 50% of the lower grille as well, but on the 1.4T, the intercooler is down there. Maybe I could make a duct to channel air only to the intercooler and still cut flow to the radiator.