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Stonepilot
Anybody done one of these? Got a picture would love to see what it looks like? Thank you
SirAndy
QUOTE(Stonepilot @ Jan 4 2012, 12:07 PM) *
Anybody done one of these? Got a picture would love to see what it looks like? Thank you

Scooping for what exactly? confused24.gif
Stonepilot
Air across a radiator
wingnut86
Stonepilot,

Are you thinking of just visual with a blocking plate in the hole or is this for oil cooling?

The reason I ask is due to not many going top-scoop mount as it creates flow issues over that streamlined hood of ours blink.gif

Most AX'rs, Racers and Street Demons use a vented lower valance up front or something less visual.

Good luck if you find something and please share it here, as I for one have never seen one...
SirAndy
QUOTE(Stonepilot @ Jan 4 2012, 12:20 PM) *
Air across a radiator


The hood is too high for a intake scoop.

Usually, you run the intake though a opening in and behind the bumper (See my avatar).

There are several ways for the air to exit and i do prefer the "out the hood" vent. Neither the "original Porsche way" (out the bottom) as well as the "v8 way" (out the fender wells) appeal to me.
The first adds a lot of hot air under the car, the second adds a lot of hot air onto the front brakes.

Do a search here, there are several cars that have gone the exit out the hood route. It's crucial to have a front facing "lip" on the exit to help with air-flow.

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SirAndy
I'm currently venting out the bottom, but that's temporary until i can find the time to fabricate a nice shroud for venting out the hood.

http://www.914world.com/bbs2/index.php?s=&...st&p=893543

driving.gif
bfrymire
Look for Britain's build thread on adding a suby powerplant to the 914. He has a hood exit for the radiator using louvers.

-- brett
JmuRiz
QUOTE(SirAndy @ Jan 4 2012, 12:27 PM) *

I'm currently venting out the bottom, but that's temporary until i can find the time to fabricate a nice shroud for venting out the hood.

http://www.914world.com/bbs2/index.php?s=&...st&p=893543

driving.gif

Now you're talking...venting out the hood is the best way, as long as you don't mind poising cargo space.

I'm trying to think of a way to do a front cooler w/o taking up much/if any cargo space up front...haven't found one yet though.
SirAndy
QUOTE(JmuRiz @ Jan 4 2012, 05:16 PM) *
I'm trying to think of a way to do a front cooler w/o taking up much/if any cargo space up front...haven't found one yet though.

Look at some newer model Porsche's. They use a very steep angle right after the cooler that goes almost straight up.
shades.gif

In my case, i'm going to make the shroud a two piece part so when you open the hood, you still have access to the space behind the shroud. Should be enough for a toolbox and other assorted items.
The spare tire is already mounted in the rear trunk. I'm going to leave it a full-size spare but i'll be going down in rim diameter. Right now my spare is a 7" cookie cutter with a 215 tire. A 5.5" with a tire somewhere around 175 should be plenty for a spare.

santa_smiley.gif
Stonepilot
could you raise the hood an inch up near the windshield and build a vent under the hood to take the air coming thru the radiator out over the windsheild. of course the air coming in is under the car. is the air coming off the radiator that hot?
Andyrew
What engine will you be running?
Stonepilot
Id like an EJ20 but any 6 will do, maybe something new
rnellums
QUOTE(Stonepilot @ Jan 5 2012, 07:53 AM) *

could you raise the hood an inch up near the windshield and build a vent under the hood to take the air coming thru the radiator out over the windsheild. of course the air coming in is under the car. is the air coming off the radiator that hot?


The problem there is that the base of the windshield is a high pressure zone. It isnt as high as the front of the car where your inlet will be, but you won't get as much airflow as if you vent to a low pressure area.

When I do my conversion I think I will vent to the wheel wells. I still need to do the calculations, but I think the relative heat coming out of the vents should be far less than the temperature of the brakes under heavy use.
bulitt
Some pics-

Ferrari 308, 512bbi used louvered grills-

Click to view attachment

Shelby Daytona- With lip Andy mentioned.

Click to view attachment

Ford GT-40

Click to view attachment

Jag XKE used louvers, Dodge viper also louvers.

Click to view attachment

brant
I've ran a vented hood on my oil cooler for 15 or so years
its all steel and pictured in my street car signature below
Britain Smith
Vented Carbon Fiber Louvers...works awesome.

IPB Image

IPB Image

-Britain
SirAndy
QUOTE(brant @ Jan 5 2012, 07:22 AM) *

I've ran a vented hood on my oil cooler for 15 or so years
its all steel and pictured in my street car signature below

That's exactly what i want to do! thumb3d.gif

Well, not the big hole in the hood, but what you had before that. A shroud going up with louvers on the hood for the exit.

driving.gif
Stonepilot
very nice thats what I was talking about. thank you
Andyrew
With a small engine like that, you could put a small radiator in the front of the trunk, or in with the body and then exhaust it out the front of the hood like the new porsche's. Then guess what, You still have a front trunk!
wingnut86
Go Subie and buy this gents hood!

Group discount? beer.gif
wingnut86
Hand made or re-purposed?


QUOTE(Britain Smith @ Jan 5 2012, 01:55 PM) *

Vented Carbon Fiber Louvers...works awesome.

IPB Image

IPB Image

-Britain

Mike Bellis
QUOTE(SirAndy @ Jan 4 2012, 12:24 PM) *

The first adds a lot of hot air under the car, the second adds a lot of hot air onto the front brakes.


The hot air on the brakes at 180-190F is cooler than hot brakes. It can actually act as cooling on the track when you are on the brakes a lot.

I think cooling through the fender wells is the most proven cooling design for a street car.
Britain Smith
I got those vents from here:

http://www.genesisparts.com/index.cfm?tpc=...;action=product

They weren't cheap, but serve the purpose.

I am not a fan of the air vents in the wheel wells, that is the last place I want air to go at high speed.

-Britain
szuccaro
Here's my idea... taken from the late model turbo T-bird... Steve
szuccaro
and applied to the side, looks like this.
brant
do you have a cooler under there?...
szuccaro
QUOTE(brant @ Jan 5 2012, 11:10 PM) *

do you have a cooler under there?...


purely non-functional
Elliot Cannon
QUOTE(szuccaro @ Jan 5 2012, 10:53 PM) *

QUOTE(brant @ Jan 5 2012, 11:10 PM) *

do you have a cooler under there?...


purely non-functional

It looks like their function is to cause aerodynamic drag. happy11.gif
SirAndy
QUOTE(kg6dxn @ Jan 5 2012, 09:48 PM) *
QUOTE(SirAndy @ Jan 4 2012, 12:24 PM) *
The first adds a lot of hot air under the car, the second adds a lot of hot air onto the front brakes.


The hot air on the brakes at 180-190F is cooler than hot brakes. It can actually act as cooling on the track when you are on the brakes a lot.

I think cooling through the fender wells is the most proven cooling design for a street car.

Proven by what exactly? I'd rather have fresh air to cool my brakes.
confused24.gif
Stonepilot
QUOTE(szuccaro @ Jan 6 2012, 12:05 AM) *

and applied to the side, looks like this.

nice looking!
pcar916
Here's mine. It's illegal in SCCA track events though.

Click to view attachment

Good luck
wingnut86
I looked through the rules previously, but, why do they say no to that design?

are there other in-hood venting designs they say yes to?
brant
cross post from my street car thread:

pcar916
QUOTE(wingnut86 @ Jan 6 2012, 08:10 AM) *

... why do they say no to that design?
are there other in-hood venting designs they say yes to?


It wasn't part of the original design of the car, and they consider it an air diverting structure, as if air through a big cooler would add downforce to the front of the car.
It also wasn't part of the original design of the car. To be fair it's been years since I looked into it so this is now second hand info to me. Anyone who knows this has changed can chime away.

I first evacuated the exhaust under the car but not only did it not cool the oil very well (inlet too small... my design error) but I figured it was simply heating air back to the engine. The 993 engine needs a full-time cooler since engine cooler behind cylinder #6 was deleted.
SirAndy
QUOTE(pcar916 @ Jan 6 2012, 07:41 AM) *
as if air through a big cooler would add downforce to the front of the car.

If i recall correctly, the guy that did all the air flow tests on modified 914 chassis a while back reported a significant increase in downforce with a hood vent.

From my armchair physics perspective, that would make sense.
shades.gif
Andyrew
^ I would agree with this as well.

It might not make much of a difference at 60mph, but at 100mph it would probably be fairly noticeable.
Britain Smith
I have been thru the fight with the SCCA guys on hood venting, what I did with the louvers was the best I could do within the rules for Autocross. There can be no actual ducting underneath either.

-Britain
SirAndy
QUOTE(Britain Smith @ Jan 6 2012, 11:21 AM) *
I have been thru the fight with the SCCA guys on hood venting, what I did with the louvers was the best I could do within the rules for Autocross. There can be no actual ducting underneath either.

On that note, one of the 911 guys that runs in the Toyo spec class with PRC here locally showed up with a hood exit vent for his front mounted oil cooler last summer.
(Pretty well known guy too)

When i asked the officials about the obvious rule violation, i got the following answer:

"He's too slow anyways. Once he starts winning, we'll worry about that."


Gotta love those guys!
laugh.gif
bulitt
QUOTE(brant @ Jan 6 2012, 10:25 AM) *

cross post from my street car thread:


I'm thinking you could close off the front half of your exit opening and not lose much airflow?
MDG
Hood scoop from the lastest Ferrari GTO concept on a random pic of a 914

Click to view attachment
brant
QUOTE(bulitt @ Jan 6 2012, 02:09 PM) *

QUOTE(brant @ Jan 6 2012, 10:25 AM) *

cross post from my street car thread:


I'm thinking you could close off the front half of your opening and not lose much airflow?



My front opening is smaller than the liscense plate
I leave the plate on most of the time and only pull the plate when I need the cooling... (ie: heat of the summer, or track time)

I've use the exact (and acutal) same cooler in three different exit configurations
each one opened up and increased the exit size, and correspondingly dropped the oil temperature

this one has a HUGE exit for a very small cooler and is 20degrees F cooler oil temps on the track than my most restrictive experiment (same cooler, same car, same motor, different day)

I agree with the old rule of thumb about using 2x the exit size of your cooler entrance size.... (that hot air expands and a good exit draws more air through the cooler)
SirAndy
QUOTE(brant @ Jan 6 2012, 01:13 PM) *
this one has a HUGE exit for a very small cooler and is 20degrees F cooler oil temps on the track than my most restrictive experiment (same cooler, same car, same motor, different day)

One would think that with a louvered cover (even if only partially covering that huge hole) you could get pretty close to the same actual open surface but with a much better visual result.

idea.gif
MDG
Looks like he made some mods confused24.gif

Click to view attachment
wingnut86
Hey,

I thought Danny Bonaducci from "The Partridge Family" had lost his license on crack.

But there he is behind the wheel.
happy11.gif
pt_700
i wonder if those extraction vents on the hood might feed hot air into the cockpit with the top off on warm days?

do any of the posters with wheel well vents drive in the rain or dusty conditions? might this make the front trunk dirtier?
SirAndy
QUOTE(pt_700 @ Jan 6 2012, 02:36 PM) *

i wonder if those extraction vents on the hood might feed hot air into the cockpit with the top off on warm days?

do any of the posters with wheel well vents drive in the rain or dusty conditions? might this make the front trunk dirtier?

There is no *might* about it. Yes, even with the screens used on some, there's a lot of dirt in the front trunk.

As for the hot air over the windshield, yes, you can feel it but it disperses pretty quickly.
One would have to run a couple of tests with a few sensors around the car to get exact numbers.

However, my point still stands. I'd rather have the air up and away than under the car where it will create additional lift.
Not much of a problem for street driving, but at the track, you'll want all the help you can get.

A 914 can get pretty "light" above ~120mph ...
driving.gif
PeeGreen 914
QUOTE(SirAndy @ Jan 6 2012, 03:33 PM) *

QUOTE(pt_700 @ Jan 6 2012, 02:36 PM) *

i wonder if those extraction vents on the hood might feed hot air into the cockpit with the top off on warm days?

do any of the posters with wheel well vents drive in the rain or dusty conditions? might this make the front trunk dirtier?

There is no *might* about it. Yes, even with the screens used on some, there's a lot of dirt in the front trunk.

As for the hot air over the windshield, yes, you can feel it but it disperses pretty quickly.
One would have to run a couple of tests with a few sensors around the car to get exact numbers.

However, my point still stands. I'd rather have the air up and away than under the car where it will create additional lift.
Not much of a problem for street driving, but at the track, you'll want all the help you can get.

A 914 can get pretty "light" above ~120mph ...
driving.gif


agree.gif The last thing I would think you would want to do is make it any lighter in the front by adding lift. Going around a sweeping bend at 100+ it feels light enough without the added lift. blink.gif
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