Hood vents?

[Zandcwhite]

They have to warranty every jeep, including the inevitable few that will buy, drive for a few days, and park through a Minnesota winter in the driveway. If my jeep sat for weeks or months, I'd have left the factory fake vents. Running Temps are absolutely lower as are under hood Temps and the IAT since the functional vents went in. Anybody who thinks a bone stock Jeep is the pinnacle of engineering without a single cost cutting compromise has bumped their head one too many times.

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[bige_talls]

Here’s a video of a guy looking at high speed aero of cutting the vents. Not sure if air coming in means less air going through the radiator.

 

[Zandcwhite]

Here’s a video of a guy looking at high speed aero of cutting the vents. Not sure if air coming in means less air going through the radiator.

In my experience, the Jeep has plenty of cooling at speed. When you’re crawling along in 4LO on a tough trail and it’s 100°+ out is when the system seems like it could use some help. Even in the mid day heat I can watch the heat waves pouring up out of the Valkyrie off road vents. There’s no way to argue that not trapping all that heat on top of the intake manifold, intercooler, etc and letting not only natural heat rise, but the engine fan blow it out the hood is not beneficial. I’ve seen lower intake air temps, lower engine coolant temps, and less engine fan on high speed under the same conditions. Does it help at freeway speed? Probably not. Does the cooling system need help at freeway speed though?

 

[JABCAT]

Cut the vents on my JKU and sitting at stop lights in the TX summer, you can see the hot air coming out of the vents. Having them open does allow for better cooling in the engine bay. On the other end, contrary to what some think, very little water actually comes in through the vents, less at driving speeds, and in over 60k miles on my JKU no twigs, sticks, leaves, or anything else entered through the vents.

 

[DHW]

Here is the write up I did a while back of how I did my vents.

https://www.jlwranglerforums.com/fo...bicon-hood-vents-write-up.82001/#post-1715839

I used prefilter to keep water out. I've seen no drop in mileage. As other have said, I wasn't concerned with cooling at speed, but in Atlanta's world famous traffic. Every time I stop the Jeep at a red light or whatever I can see heat waves coming out of both vents.

 

[OldBlue]

Mopar CAI intke and extended hood hinges are fully functional as vent openings.

That shot reminds me of the extended hinges I used to use on the engine covers on my air-cooled VWs!

 

[AcesandEights]

The engine is cooled by the radiator. Those vents don't do anything worthwhile if opened, but the hood insulation does have a function.

 

[Osinski]

I made this with my Rubicon.
In Summer I can see the hot air through the holes.
I have to finish them.

Greetings from Spain.

 

[Barstool]

I like the look of the rubicon hood so I was thinking of buying one and putting it on my Sahara with the vents closed. Then I found these led hood scoop lights. So I think the rubicon hood + lights route is the one I’m taking.

 

[BDinTX]

I made this with my Rubicon.
In Summer I can see the hot air through the holes.
I have to finish them.

Greetings from Spain.

how did you get the honeycomb part in red? I like that!

 

[mwilk012]

This really sounds like a “bro trust me” kind of mod, like a K&N air filter.

 

[Osinski]

how did you get the honeycomb part in red? I like that!

I painted it with spray.

 

[Whaler27]

I didn't see the point of the non-functional vents and was not a fan of the tonka toy sized RUBICON on the hood. I fully appreciated that another member loved the look and was willing to give me $500 to swap to his Sahara hood.

Mopar CAI intke and extended hood hinges are fully functional as vent openings.

I opted to replace the OEM faux-vents with the S&B functional vents and CAI.

After owning them for a while I guess I still like them, but, for me, they’re not worth what they cost.

 

[JABCAT]

The engine is cooled by the radiator. Those vents don't do anything worthwhile if opened, but the hood insulation does have a function.

This really sounds like a “bro trust me” kind of mod, like a K&N air filter.

The point is to let hot air escape to help reduce underhood temperatures. If the underhood temperatures are lower, the engine runs more efficiently. So yes, having open vents in the hood actually helps in this regard. The hood on my Callaway supercharged Z06 has 20 small vents plus is open at the windshield cowl & the fenders have very large vents to allow hot air to escape the engine bay resulting in much lower operating temperatures. Pretty sure these guys know what they’re doing.

 

[mwilk012]

The point is to let hot air escape to help reduce underhood temperatures. If the underhood temperatures are lower, the engine runs more efficiently. So yes, having open vents in the hood actually helps in this regard. The hood on my Callaway supercharged Z06 has 20 small vents plus is open at the windshield cowl & the fenders have very large vents to allow hot air to escape the engine bay resulting in much lower operating temperatures. Pretty sure these guys know what they’re doing.

What do you mean by “more efficient”? Engines run more efficiently at higher temperatures, not lower. Otherwise, they would still be putting 160F thermostats in them.

The comparison to the corvette is a joke right? Look at the difference in the size of the grille and ground clearance versus operating power output. It’s not even close.

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