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LTb1ow
07-25-2019, 09:16 AM
Has anyone got experience with naca scoops?

Giving some thought to adding two to the roof in order to vent out car while driving.

LS1ow
07-25-2019, 09:55 AM
YESSSSSSS

wretched73
07-25-2019, 10:00 AM
No experience but I'd bet a tubular front end would help more :)

LTb1ow
07-26-2019, 07:24 AM
Actually I misspoke, not a naca scoop, just a reverse scoop.

Goal is to allow air to actually pass thru car while driving windows down.

The_Bishop
07-26-2019, 10:59 AM
Might be 'interesting' if there's no way to close 'em and you get caught in some rain.

wretched73
07-26-2019, 03:59 PM
Actually I misspoke, not a naca scoop, just a reverse scoop.

Goal is to allow air to actually pass thru car while driving windows down.

I know in the 3rd gens, not sure about 4th, that the holes in the door jams are used for a similar effect.

Why not try and have the air come thru the fenders? Or under the car? Isn't it hot enough in the cabin without A/C?

V
07-26-2019, 05:30 PM
What about cutting some holes in the rear deck lid under the spoiler? It would be mostly hidden and in theory should cause a pulling effect on the air the help vent it. You could even put louvers and some type a drip rail/pan to catch and divert rain.

LTb1ow
07-29-2019, 08:32 PM
Might be 'interesting' if there's no way to close 'em and you get caught in some rain.

Picture like a trailer vent, you can seal em with not open.

I know in the 3rd gens, not sure about 4th, that the holes in the door jams are used for a similar effect.

Why not try and have the air come thru the fenders? Or under the car? Isn't it hot enough in the cabin without A/C?

The windows down don't allow air to come into the car cause there is no exit for it so it just buffets my head. Trying to create a path thru the cabin of the car for outside air

What about cutting some holes in the rear deck lid under the spoiler? It would be mostly hidden and in theory should cause a pulling effect on the air the help vent it. You could even put louvers and some type a drip rail/pan to catch and divert rain.

I worry that any air inlet/exit by the rear could start to draft exhaust fumes back into the car.

LS1ow
07-29-2019, 08:46 PM
What are you actually venting the car for? To many fumes inside? Just want fresh air?

LTb1ow
07-30-2019, 07:06 AM
What are you actually venting the car for? To many fumes inside? Just want fresh air?

To not drive in a mobile oven.

Blackbirdws6
07-30-2019, 08:09 AM
Install scoop where trap door would go!

The above is partially serious but you really need to get a wind speed meter to test different spots within the interior to see where the "high pressure" zones are. Otherwise you are punching a hole somewhere and it may not be in the right spot. I can likely borrow one from work if you want to do some half-ass engineering sometime. I'd think the rear deck before you get into the rear hatch/trunk area would like be a good spot. A scoop or two installed there with an exit in the bottom of the trunk would provide a reasonable path for air while avoiding issues of bringing exhaust fumes into the cabin. If you are very concerned, install a flap with a spring at the exit. When sitting still, exit is closed, at speed with some air flow/pressure, it's open. You'd have to figure out the right spring tension of course.

wretched73
07-30-2019, 08:16 AM
Why not put the scoop in the front fender and have them route directly into the cabin?

Could even tie into the HVAC system.

So scoop in fender to hose to vent in cabin.

LS1ow
07-30-2019, 08:22 AM
well the car already has fresh air vents in the rear lower 1/4s to let air out, or at least i think it does, so is a roof scoop not the obvious solution to your problems ?

LTb1ow
07-30-2019, 08:23 AM
Install scoop where trap door would go!

The above is partially serious but you really need to get a wind speed meter to test different spots within the interior to see where the "high pressure" zones are. Otherwise you are punching a hole somewhere and it may not be in the right spot. I can likely borrow one from work if you want to do some half-ass engineering sometime. I'd think the rear deck before you get into the rear hatch/trunk area would like be a good spot. A scoop or two installed there with an exit in the bottom of the trunk would provide a reasonable path for air while avoiding issues of bringing exhaust fumes into the cabin. If you are very concerned, install a flap with a spring at the exit. When sitting still, exit is closed, at speed with some air flow/pressure, it's open. You'd have to figure out the right spring tension of course.

The trunk floor pan is something I have given thought too, but again worry about drafting fumes. If ass of car is like boats, running a genset on back deck of boat even underway will kill owners.

And Chris, its not getting air into the cabin, its getting air out of the cabin.

Blackbirdws6
07-30-2019, 08:47 AM
The trunk floor pan is something I have given thought too, but again worry about drafting fumes. If ass of car is like boats, running a genset on back deck of boat even underway will kill owners.

And Chris, its not getting air into the cabin, its getting air out of the cabin.

I get it but my thought was if you are at speed, the air flowing under the car will be enough to pull it away avoiding the low air pressure from the back of the car. The end of the duct would need to be low enough to make that work.

I agree if the exit was right at the back bumper, that would be no bueno as the air pressure is low in that area. See pic below.

https://cdn10.bigcommerce.com/s-79fzp/product_images/uploaded_images/frs-brz-aerodynamics-rear-spats.jpg?t=1459897157

I'd guess on your car, the air pressure is light right behind the bumper (reason why we get smootz from exhaust there when our LTx's hate life). Below and closer to the rear, I bet there is a good amount of flow.

sweetbmxrider
07-30-2019, 10:46 AM
The factory ones open under pressure and are normally closed. When you close your door with windows up, air pressure has to go somewhere.

I say lexan removable rear window.

wretched73
07-31-2019, 06:35 AM
I say lexan removable rear window.

Why stop there? Take the doors off and go full #JeepLyfe


I see your predicament. Do you have a spare hatch? Maybe vents in the deck lid could help. If you had or obtained a spare one at least you could test it out before committing 100%.

ar0ck
08-08-2019, 01:55 PM
3rd gen style hatch louvers without the glass.