Hood louvers... Do they really work? - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > TJ Wrangler Technical Forum > Hood louvers... Do they really work?

Artec Flash Sale - 15% off and Free Shipping over $300Rugged Ridge Bumpers, Winches, Performance from CCOR!JK Front Axle Truss

Reply
Unread 07-06-2010, 05:06 AM   #1
TeeJay00
Registered User
2000 TJ Wrangler 
 
Join Date: Nov 2009
Location: Kuwait
Posts: 1,545
Hood louvers... Do they really work?

I have searched this forum for hood louvers and all I got was threads of how to install them and debates on which kind to use and so on from guys who plan on installing them...

Now my question is for the people who are using these hood louvers or vents.
Do they actually work on reducing engine tempreture? If so, how much cooling is expected off of them?

TeeJay00 is offline   Reply With Quote
Unread 07-06-2010, 05:24 AM   #2
stogie25
Registered User
1997 TJ Wrangler 
 
Join Date: Apr 2006
Location: Denver, Colorado
Posts: 1,448
I did home made vents. Using my Scangauge II to monitor the intake temperature the vents lowered the temperature approximately 30 degrees. I had my hood off last week while it was getting repainted, and the temperature went down another 30 degrees on average.

__________________
Jarhead Jeep Club
O|||||||O
97 Black TJ (one owner), BFG KM2 35s, 4.7L Stroker, ARB's, Dana60 rear, Dana30HP Front Warn manual hub conversion, 6 inch mostly Tera long arm lift. Rhino lined tub. Allied Rock 8 beadlocks. Tera-Low 4:1. Sanden OBA. Sniperfab tube fenders.

My Build Thread http://www.jeepforum.com/forum/f22/m.../#post12717920
stogie25 is offline   Reply With Quote
Unread 07-06-2010, 05:52 AM   #3
Sundowner
Part-Time Swami
 
Sundowner's Avatar
2003 TJ Wrangler 
 
Join Date: May 2009
Location: The Republic of Dave
Posts: 6,184
What sort of intake temperatures were you seeing, incidentally?
__________________
If it's worth doing, then it's worth overdoing.

The Republic of Dave: Bringing you the finest in simian testing supplies.

The build, the gear, and the mileage: The Wasteland Survival Guide
Sundowner is offline   Reply With Quote
Unread 07-06-2010, 07:28 AM   #4
PhulesAu
Registered User
2004 LJ Wrangler 
 
Join Date: Jun 2006
Location: Texas Gulf Coast
Posts: 1,840
Yes they work very well. Especially at slow speeds and when towing.
__________________
04 L J
Travel'n Gadget Show
KE5PPH
PhulesAu is offline   Reply With Quote
Unread 07-06-2010, 08:10 AM   #5
stogie25
Registered User
1997 TJ Wrangler 
 
Join Date: Apr 2006
Location: Denver, Colorado
Posts: 1,448
Quote:
Originally Posted by Sundowner View Post
What sort of intake temperatures were you seeing, incidentally?
My readings are through the ECU from the air intake sensor as opposed to actual underhood temperatures. It is screwed into the intake manifold, above the header. The Jeep gets hottest when it has ran a while, then sat for a few minutes, then ran again. This is the condition at which I was taking my readings. With the hood complete, I was getting high temperatures in the 180's. With the vents, I am getting temperatures in the 150's. With the hood off the temperatures were in the 120's.

One can feel the hot air billowing out of the vents when I park the Jeep.
__________________
Jarhead Jeep Club
O|||||||O
97 Black TJ (one owner), BFG KM2 35s, 4.7L Stroker, ARB's, Dana60 rear, Dana30HP Front Warn manual hub conversion, 6 inch mostly Tera long arm lift. Rhino lined tub. Allied Rock 8 beadlocks. Tera-Low 4:1. Sanden OBA. Sniperfab tube fenders.

My Build Thread http://www.jeepforum.com/forum/f22/m.../#post12717920
stogie25 is offline   Reply With Quote
Unread 07-06-2010, 08:40 AM   #6
Sundowner
Part-Time Swami
 
Sundowner's Avatar
2003 TJ Wrangler 
 
Join Date: May 2009
Location: The Republic of Dave
Posts: 6,184
180's? Yowza. That's quite the oven-like environment. I might have to look into fabbing something up. Any clear pictures of the vents in question?
__________________
If it's worth doing, then it's worth overdoing.

The Republic of Dave: Bringing you the finest in simian testing supplies.

The build, the gear, and the mileage: The Wasteland Survival Guide
Sundowner is offline   Reply With Quote
Unread 07-06-2010, 09:36 AM   #7
rastadog
Member
 
rastadog's Avatar
2001 TJ Wrangler 
 
Join Date: Nov 2004
Location: Washington, DC
Posts: 294
According to the owner of Off Road Trail Tools Hood Louvers, Black, Jeep, wrangler, TJ, YJ, JK, LJ, CJ, RubiconDoes your Jeep run hot? Most do. We run these on our personal Jeeps. Hood louvers have been around forever. Why? Because they work. We see decreases in the area of 10-20 degrees cooler d they work very well when placed as shown.


It's hotter than Satan's b@llsack in DC with HIGH humidity so I'm considering installing these vents. I just replaced my fan clutch and installed a high-flow housing and a high flow thermostat. I also removed my metalcrafters grille insert. I lowered my temp almost 20 degrees.

jim
__________________
2001 Anniversary Edition Wrangler
2.5" OME HD Lift on ProComp M/T 32"s. Aussie Locker in front. Skid Row armor & fresh radiator fluid.
XM Satellite Radio - SKYFi2 and some cosmetic mods.
rastadog is offline   Reply With Quote
Unread 07-06-2010, 10:37 AM   #8
Sundowner
Part-Time Swami
 
Sundowner's Avatar
2003 TJ Wrangler 
 
Join Date: May 2009
Location: The Republic of Dave
Posts: 6,184
Is there a compelling reason that they're mounting the louvers in the locations shown? The only thing I can come up with would be that, as located, they provide an air outlet directly over the open areas adjacent to the engine, thus allowing cold air from underneath the Jeep to flow up through the engine bay and out...can anyone verify/contradict this?
__________________
If it's worth doing, then it's worth overdoing.

The Republic of Dave: Bringing you the finest in simian testing supplies.

The build, the gear, and the mileage: The Wasteland Survival Guide
Sundowner is offline   Reply With Quote
Unread 07-06-2010, 10:44 AM   #9
rastadog
Member
 
rastadog's Avatar
2001 TJ Wrangler 
 
Join Date: Nov 2004
Location: Washington, DC
Posts: 294
Quote:
Originally Posted by Sundowner View Post
Is there a compelling reason that they're mounting the louvers in the locations shown? The only thing I can come up with would be that, as located, they provide an air outlet directly over the open areas adjacent to the engine, thus allowing cold air from underneath the Jeep to flow up through the engine bay and out...can anyone verify/contradict this?
According the the owner of OffRoadTrailTools, the placement is key for the proper cooling. He made that very clear when I spoke with him on the phone.

The way I understand it, the whole point is giving hot air a place to escape, it's not about getting cold air in. Having vents right above the radiator and each side of the engine bay make sense to me.
__________________
2001 Anniversary Edition Wrangler
2.5" OME HD Lift on ProComp M/T 32"s. Aussie Locker in front. Skid Row armor & fresh radiator fluid.
XM Satellite Radio - SKYFi2 and some cosmetic mods.
rastadog is offline   Reply With Quote
Unread 07-06-2010, 10:44 AM   #10
2005X
Registered User
2005 TJ Wrangler 
 
Join Date: Sep 2005
Location: Thornton, Colorado
Posts: 8,276
i have no scan guage to show differences, my main reason was to help heat escape the engine compartment to help witht he overheating of my PSC steering pump. unfortunately my jeep is broke so i have to test it on the trails which is where the real test is, so basically i have nothing to add to this thread except pics of where i did my vents.
cid__0604001721.jpg   cid__0604001728a.jpg   cid__0604001727.jpg   cid__0610000933.jpg   cid__0610000932.jpg  

__________________
www.youtube.com/kgries
2005X is offline   Reply With Quote
Unread 07-06-2010, 10:50 AM   #11
Sundowner
Part-Time Swami
 
Sundowner's Avatar
2003 TJ Wrangler 
 
Join Date: May 2009
Location: The Republic of Dave
Posts: 6,184
That's awesome. Hood vents via hole saw.
__________________
If it's worth doing, then it's worth overdoing.

The Republic of Dave: Bringing you the finest in simian testing supplies.

The build, the gear, and the mileage: The Wasteland Survival Guide
Sundowner is offline   Reply With Quote
Unread 07-06-2010, 10:52 AM   #12
2005X
Registered User
2005 TJ Wrangler 
 
Join Date: Sep 2005
Location: Thornton, Colorado
Posts: 8,276
Quote:
Originally Posted by Sundowner View Post
That's awesome. Hood vents via hole saw.
total cost for my vents was $15. hole saw was free, bought some gutter guards from lowes for $2, then bought some RTV sealant, and a C clamp.
__________________
www.youtube.com/kgries
2005X is offline   Reply With Quote
Unread 07-06-2010, 12:05 PM   #13
Zen
Registered User
2005 LJ Wrangler 
 
Join Date: Jun 2009
Location: Rockwall, Texas
Posts: 1,074
There were a couple of home brew aero studies done on TJ's, but I'd have to do a search for links. One of the studies I read was very detailed. The author tested underhood temps in various places and found the highest temperatures to be in front of a directly over the engine. Then he taped 3" pieces of yarn all over the hood and did an old school wind streamline road test. He found that there was a low pressure area directly behind the radiator and one on either side of the engine. Overlaping diagrams of the heat pattern and the low pressure zones showed that the best placement of hood vents would be the locations shown in Rastadog's photo.

AEV's heat reduction hood takes advantage of the low pressure zone behind the radiator to suck out hot air and increase airflow through the radiator. It would appear that they came to a similar conclusion.

LINKY, LINKY: Oman 4X4 Hood Vent Theory
__________________
-Darkstar, judy-judy. I'm going in for guns.
--
-Stick, splash one!
Zen is offline   Reply With Quote
Unread 07-06-2010, 12:32 PM   #14
dbbd1
Senior Member
 
dbbd1's Avatar
2003 TJ Wrangler 
 
Join Date: Aug 2008
Location: Oregon
Posts: 874
Here is what I did...

Almost as cheap as the hole saw idea

Budget Hood Vents - JeepsUnlimited.com Forums
__________________
The opinions of worthless people, are worthless.

The only problem that you have with anyone in this world, is what you expect of them.

Society is no match for a stupid person.

"Life Is tough but it is tougher when you are stupid"

-John Wayne
dbbd1 is offline   Reply With Quote
Unread 07-06-2010, 02:08 PM   #15
TeeJay00
Registered User
2000 TJ Wrangler 
 
Join Date: Nov 2009
Location: Kuwait
Posts: 1,545
So the hood louvers idea should actually work in reducing engine heat as long as you place them in those specific locations. And that kit from off-road tools does look good and simple.
TeeJay00 is offline   Reply With Quote
Reply

Tags
hood , louvers , TJ
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.