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Bad Scott

Bad Scott

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I have recently installed a set of OTB scoops that I bought from iron rock off road. These you cut the bottoms out of the stock Rubicon scoops and cut out the hood liner. My big concern was water entering the engine compartment. They have a fabric in there that lets air out but doesn't let water in . The water still drains out the factory location! It also encapsulates the hood liner.

1661844896577.png
Thanks, sounds like a great solution.
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anyone have part number to the clip that hold the hood heatshield on? I snapped one off removing it. Thanks all!
 

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I wrote this on another post but here's some thoughts about this maybe you can add some more. We have been considering this mod but have not experienced under the hood high Temps. I noticed a few things with the hood design I'm not a fan of with flow and air intake so we did a test at work, I do work in thermodynamics so we had some tools to test. My buddies vents are cut and mine are not to start we ran both JLs in a fog test with a 45 mph air test. What we noticed is the fog would exit in mine out the fender vents however his had alot of turbulence and mixed air some would exit out the top most would not but when fans were off it would vent from the hood vents. Running fans usually remain on untill the engine has reached the desired temp and his vents ran the fans shorter in actual a few minutes. The hood vents from OTB scoops would be our 2nd choice.

The other thing we noticed is intake air. As you know we have an intake duck in the grill that supplies the bottom of the intake however the top of the intake is open and sealed to the hood with a very small opening to the fender area. We added the Mopar side hood vent in the exact location of the intake and it almost sealed perfectly to the intake. When running it pulled a substantial amount of air from the hood now and spooled alot quicker, we added the filter and left everything else alone. Compared to Moshimotos data when the did the R&D on the intake we achieved roughly the same at 28% more flow and cooler Temps depending on ambient, no CEL. Yes the tube could be changed but it was engineered for this flow we just gave it an alternate means of air intake. 450$ vs the 50 on the vent meh I'll take it.
 
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I wrote this on another post but here's some thoughts about this maybe you can add some more. We have been considering this mod but have not experienced under the hood high Temps. I noticed a few things with the hood design I'm not a fan of with flow and air intake so we did a test at work, I do work in thermodynamics so we had some tools to test. My buddies vents are cut and mine are not to start we ran both JLs in a fog test with a 45 mph air test. What we noticed is the fog would exit in mine out the fender vents however his had alot of turbulence and mixed air some would exit out the top most would not but when fans were off it would vent from the hood vents. Running fans usually remain on untill the engine has reached the desired temp and his vents ran the fans shorter in actual a few minutes. The hood vents from OTB scoops would be our 2nd choice.

The other thing we noticed is intake air. As you know we have an intake duck in the grill that supplies the bottom of the intake however the top of the intake is open and sealed to the hood with a very small opening to the fender area. We added the Mopar side hood vent in the exact location of the intake and it almost sealed perfectly to the intake. When running it pulled a substantial amount of air from the hood now and spooled alot quicker, we added the filter and left everything else alone. Compared to Moshimotos data when the did the R&D on the intake we achieved roughly the same at 28% more flow and cooler Temps depending on ambient, no CEL. Yes the tube could be changed but it was engineered for this flow we just gave it an alternate means of air intake. 450$ vs the 50 on the vent meh I'll take it.
Do you have any pictures? I'm a visual learner. Thanks.
 

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Is this an issue for the 2.0 only?

I live in southern california. It gets HOT sometimes here. I have the V6 pentastar and the peasant sport hood. I have never had an issue with the hood getting "too hot". It does get a little hotter than my Camry. Jeep has a bigger engine and everything is really crammed in there. But it isn't that much hotter really.
 

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I've never had heat issues even in Mohave.

Is this an issue for the 2.0 only?

I live in southern california. It gets HOT sometimes here. I have the V6 pentastar and the peasant sport hood. I have never had an issue with the hood getting "too hot". It does get a little hotter than my Camry. Jeep has a bigger engine and everything is really crammed in there. But it isn't that much hotter really.
 

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No however I think there is a YT with someone that did the TUFT test and shows these are cowls not nonfunctional scoops....

Do you have any pictures? I'm a visual learner. Thanks.
 
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No however I think there is a YT with someone that did the TUFT test and shows these are cowls not nonfunctional scoops....
I'm trying to understand this quote... " We added the Mopar side hood vent in the exact location of the intake and it almost sealed perfectly to the intake. "
 

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OK, so I'm the new kid and I just read through (almost) every post in this thread. I have a question: does anyone else regularly open their hood when done driving to allow all that pent-up heat to dissipate more quickly? I started doing it on my last car after it developed cooling issues and the habit has carried over to my new Wrangler. I'm convinced it's a good thing to do. I've noticed that despite the mid-to-high 90's we've regularly seen around here this summer - he runs perfectly cool. That's not the issue. When I pull him in the garage his hood is often cooler to the touch than about 15 minutes after I've parked. All that heat under the hood while he's running down the road is being addressed by the engineering designed to keep him cool. But when he stops, so does the cooling. So opening the hood allows all that heat to escape more quickly, saving wear and tear on the plastics, rubbers, computer chips and everything else over the life of the engine bay. The prop gets pretty hot, so I have an axe handle I keep by the front and open him up to give him some air when done driving. I know I probably don't need to, but it feels like a good thing to do. Not saying every time, everywhere... but.... Don't want my buddy ridden hard and put away wet when there's an easy fix. Anyone...?
Open Hood.jpg
Jbcrane, can I ax you why you chose to use an ax there?
 

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Jbcrane, can I ax you why you chose to use an ax there?
Ax and you shall receive... it was on hand, the right length and better than the hood prop - which made a cracking sound every time I un-hooked it from the yellow clip on the hood. Figured it was just a matter of time until it broke and the prop swung down. And in the summer, that little bugger was hot to the touch. Any other questions ax away.
 

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I wrote this on another post but here's some thoughts about this maybe you can add some more. We have been considering this mod but have not experienced under the hood high Temps. I noticed a few things with the hood design I'm not a fan of with flow and air intake so we did a test at work, I do work in thermodynamics so we had some tools to test. My buddies vents are cut and mine are not to start we ran both JLs in a fog test with a 45 mph air test. What we noticed is the fog would exit in mine out the fender vents however his had alot of turbulence and mixed air some would exit out the top most would not but when fans were off it would vent from the hood vents. Running fans usually remain on untill the engine has reached the desired temp and his vents ran the fans shorter in actual a few minutes. The hood vents from OTB scoops would be our 2nd choice.

The other thing we noticed is intake air. As you know we have an intake duck in the grill that supplies the bottom of the intake however the top of the intake is open and sealed to the hood with a very small opening to the fender area. We added the Mopar side hood vent in the exact location of the intake and it almost sealed perfectly to the intake. When running it pulled a substantial amount of air from the hood now and spooled alot quicker, we added the filter and left everything else alone. Compared to Moshimotos data when the did the R&D on the intake we achieved roughly the same at 28% more flow and cooler Temps depending on ambient, no CEL. Yes the tube could be changed but it was engineered for this flow we just gave it an alternate means of air intake. 450$ vs the 50 on the vent meh I'll take it.
Soooo, after reading this about 5X, you are saying, that if you DO NOT modify the non-functional hood vents on the Rubicon hood, more air flow will exit out of the front fender vents, with a lot less turbulence, versus cutting the fake hood vents open?
 

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Soooo, after reading this about 5X, you are saying, that if you DO NOT modify the non-functional hood vents on the Rubicon hood, more air flow will exit out of the front fender vents, with a lot less turbulence, versus cutting the fake hood vents open?
Its almost like there were engineers involved with designing the air flow under the hood.


This reminds me of all the JDM kids that would do hood risers or add plates in the front to "improve" airflow and it never did.
 

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All and all yes you are correct. The JLUR hood is for aerodynamics not a faux hood. When you cut open the hood you loose the flow add turbulence and do not add more flow it's BS. JLURs do NOT have a over heating issue. If you rock crawl and find the need and temps push the limit for more stagnant air flow cut the hood and add 2 small axiel fans. If not no need.

But they look cool and provocative!

Soooo, after reading this about 5X, you are saying, that if you DO NOT modify the non-functional hood vents on the Rubicon hood, more air flow will exit out of the front fender vents, with a lot less turbulence, versus cutting the fake hood vents open?
 

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OK, so I'm the new kid and I just read through (almost) every post in this thread. I have a question: does anyone else regularly open their hood when done driving to allow all that pent-up heat to dissipate more quickly? I started doing it on my last car after it developed cooling issues and the habit has carried over to my new Wrangler. I'm convinced it's a good thing to do. I've noticed that despite the mid-to-high 90's we've regularly seen around here this summer - he runs perfectly cool. That's not the issue. When I pull him in the garage his hood is often cooler to the touch than about 15 minutes after I've parked. All that heat under the hood while he's running down the road is being addressed by the engineering designed to keep him cool. But when he stops, so does the cooling. So opening the hood allows all that heat to escape more quickly, saving wear and tear on the plastics, rubbers, computer chips and everything else over the life of the engine bay. The prop gets pretty hot, so I have an axe handle I keep by the front and open him up to give him some air when done driving. I know I probably don't need to, but it feels like a good thing to do. Not saying every time, everywhere... but.... Don't want my buddy ridden hard and put away wet when there's an easy fix. Anyone...?
Open Hood.jpg
I do this while out wheeling. The cabin is much cooler when I get back in.
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