Grille inserts

Sorry to the OP who just came here to share a cool mod to his Moms Jeep, but this is the fun of it right? If anybody wants to rehash it we could venture back to the thread with the math instead of dumping all over this thread.

I wasn’t even the OP 😂 I was just sharing that I had the same ones as well lol
 
The grill inserts do the same thing. They simply increase the airspeed through the grill openings. The fan clutch determines the airflow through the radiator increasing it and decreasing it as needed. This is the part most people have trouble wrapping their heads around. There is no change in flow through the radiator, just a change in load on the fan.

Sorry to the OP who just came here to share a cool mod to his Moms Jeep, but this is the fun of it right? If anybody wants to rehash it we could venture back to the thread with the math instead of dumping all over this thread.
Haha! Not to beat a dead horse here, but a good analogy would be in a downtown area with tall buildings on a windy day. Many have experienced how the buildings effect the airspeed through the streets, sometimes in an amazing fashion. The air has nowhere else to go, so...
 
I wont pretend like i know all the rules of aerodynamics. However,the ends of the spectrum are zero blockage and complete blockage.The vents are somewhere in between. You can't say same amount of air at different speed because the air isn't being ducted to the grill. Some of that air will go around/over the grill just like when its completely blocked.
 
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You can't say same amount of air at different speed because the air isn't being ducted to the grill. Some of that air will go around/over the grill just like when its completely blocked.

To beat the dead horse, the air is being sucked in by the fan. The speed of the Jeep isn't really a big factor. If you are going slow it just means the fan has to engage a tiny bit more. Nothing is blocking the air, it's just making it a tiny tiny bit harder for the fan to suck it in. The fan has no issue with the tiny tiny bit of extra effort required to suck air through those decorative things or a winch or lights. That's the whole thing, the fan is sucking a large volume into the radiator. Air isn't just blowing through like a hot spring day that fan is forcing it through hell or high water with a 190HP engine driving it using 4.0 Jeep power. It ain't just asking nicely for it to go through the radiator, it is telling it to go through and exactly how much.

Edit: I understand not everybody is going to see it this way and that's totally fine. I'm just trying to express the way I see it
 
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I'll agree to that when air is being pulled in. I dont know if thats always the case while the vehicle is moving. Just like overheating sitting in traffic is not the same as overheating while driving.
 
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I'll agree to that when air is being pulled in. I dont know if thats always the case while the vehicle is moving. Overheating sitting in traffic is not the same as overheating while driving.
There are never any easy answers. Overheating means something is wrong and that's really not what I'm talking about. Obviously when things break you overheat regardless of winches or inserts.
 
Im good with that.

Once again I find myself apologizing to the OP for derailing this thread.
 
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Blocked, obstructed, redirected, lessened, turbulized and atomized. Is the Jeep overheating? Does the temperature gauge read one lick different than it did before the inserts?

I know I have a square metal mesh piece that covers my whole grill area. It has been on since 2002. I tend to be slightly abusive to the little bastard, and never wanted a branch coming through the grill and punching through the radiator when crashing through some trees or a brush pile. It has never overheated and the metal screening has successfully protected the radiator all these years. Looks like cancer is going to get it soon though as it has gotten much else on the poor thing.....

The inserts look good. Better than the crap you see behind the grill.
 
Interesting timing on this discussion. There is another thread going that was posted by a guy from Kuwait that is overheating in extreme conditions. He was told by a respected member here to remove his grille inserts. He is still testing, but so far he thinks it actually made a noticeable difference. Now, perhaps he does have other issues with his cooling system as is being discussed here and there (it is not stock), but he has made this one simple change so far and is going to keep testing and report back. Should be interesting to find out what happens. I’m not sold either way, just saying, haha!

https://wranglertjforum.com/threads/is-it-worth-it-to-change-the-cold-air-intake.25744/
 
Interesting timing on this discussion. There is another thread going that was posted by a guy from Kuwait that is overheating in extreme conditions. He was told by a respected member here to remove his grille inserts. He is still testing, but so far he thinks it actually made a noticeable difference. Now, perhaps he does have other issues with his cooling system as is being discussed here and there (it is not stock), but he has made this one simple change so far and is going to keep testing and report back. Should be interesting to find out what happens. I’m not sold either way, just saying, haha!

https://wranglertjforum.com/threads/is-it-worth-it-to-change-the-cold-air-intake.25744/
Electric fan.
 
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Interesting timing on this discussion. There is another thread going that was posted by a guy from Kuwait that is overheating in extreme conditions. He was told by a respected member here to remove his grille inserts. He is still testing, but so far he thinks it actually made a noticeable difference. Now, perhaps he does have other issues with his cooling system as is being discussed here and there (it is not stock), but he has made this one simple change so far and is going to keep testing and report back. Should be interesting to find out what happens. I’m not sold either way, just saying, haha!

https://wranglertjforum.com/threads/is-it-worth-it-to-change-the-cold-air-intake.25744/
Yea but no. The Kuwait guy has an aftermarket aluminum radiator and a electric fan.
 
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Electric fan.
And no shroud.

Yes, of course, I and others immediately brought all that up in the thread. I thought it was interesting since he “thinks” removing inserts are now making a difference for him. Blaine told him to go back to stock and also mentioned that he should remove inserts (we don’t know what they look like). Of course, the inserts were easy to remove, so he tried that first and “thinks” it made a difference. I mentioned this because this could be a case where the inserts are “the straw the breaks the camels back” in some situations...something that was being discussed in this thread. My guess is when he does more testing, he will still have issues, just thought the parallelism of the threads were interesting timing. But yeah, nobody is going to be surprised since his cooling system is not stock.
 
You can't look at a fan the same way you look at a positive displacement pump. A fan can essentially cavitate or slip with the result of lessened flow. Impeding flow in front of a fan will reduce it's output. Whether or not that is enough to cause overheating is a different issue all together.

Block off the back of a box fan and see how much air it blows out the front. It's going to blow less than if it were unrestricted. Now put a AC filter element behind the fan, it will still flow but the restriction will cause it to move less air out the front. Now remove all restrictions and test again and you'll see optimum flow.

The air speed math only works if you force the same amount of CFM through the smaller opening.