Why the hood scoop and spoiler?

Basicly the JDM version of our cars are turbo which then makes the hood scoop have a meaningful purpose. The wing i doubt that it adds any real downforce at the speeds these cars usually see in their lifetimes.

When it came time to put a USDM top of the line model of the legacy together they threw on the sporty bits to differentiate it from the L model (which has no hood scoop). As for the spoiler its pretty much same thing astectics but i have seen two variations of the GT spoiler which was between my 99 GT LTD and a friends 98 GT. The spoilers had little differences but still as legacy owners noticeable.

If you are looking for a wingless trunk this is going to be hard as most L and all GT models came from factory with s spoiler. I have seen some 30th anniversary L models that were wingless. You can also look for a jdm legacy rs trunk which some came wingless with a built in 3rd brake light and instead of "Subaru" in the garnish it says "legacy"

Basicly the JDM version of our cars are turbo which then makes the hood scoop have a meaningful purpose. The wing i doubt that it adds any real downforce at the speeds these cars usually see in their lifetimes.

 

When it came time to put a USDM top of the line model of the legacy together they threw on the sporty bits to differentiate it from the L model (which has no hood scoop). As for the spoiler its pretty much same thing astectics but i have seen two variations of the GT spoiler which was between my 99 GT LTD and a friends 98 GT. The spoilers had little differences but still as legacy owners noticeable.

 

If you are looking for a wingless trunk this is going to be hard as most L and all GT models came from factory with s spoiler. I have seen some 30th anniversary L models that were wingless. You can also look for a jdm legacy rs trunk which some came wingless with a built in 3rd brake light and instead of "Subaru" in the garnish it says "legacy"

I though it said liberty in the center garnish...

There are a lot of L models out here that have wingless trunks. In fact most of the ones I have seen are wingless. If you hate your spoiler pull if off and plug the holes.

The hood scoop keeps your engine temp a bit lower if you pull of the shield underneath. Other than that is is completely unnecessary unless you have a turbo swap. They look nice IMO.

my issue with the spoiler is really because I have a roof rack and cargo basket thing and with all that the spoiler looks like a bit too much. Also, I keep thinking of the 240sx coupe I used to have that did not have a spoiler and had the silvia front end conversion and it looked sweet. Also, loving all the modded non-spoiler cars on here.

I took the sheild off from under my scoop, i figured more cool air can't hurt but im worried about stuff getting in my bay. Ive been thinking of drilling a ton of little holes in it and reinstalling or something.

I owned a 96 Legacy L w/o the spoiler and now a 99 LGT with one and I think the spoilers make the car look much better. Although I would love to find a lip spoiler simular to the ones you can get for the EVO's. In carbon fiber please. Now that I think about it they don't make enough parts for our gens in carbon. All I've seen is a hood but it looks like poop. Be nice to see a better hood, fenders, trunk and lip spoiler but quality not crap.

2nd gen carbon trunk in progress:

http://sl-i.net/FORUM/viewtopic.php?f=39&t=23440

Do these things actually serve much purpose on our USDM legacies, or was it just a sporty look thing? I actually kind of hate my spoiler, I'm looking for a silver trunk w/out one. I'm just curious why they spec'd the GT that way.

The hood scoop has a purpose but I feel that the wing does not.

The USDM hood scoop has this black piece that you can remove to allow more cooler air in the engine bay as well as allowing heat to get out.

Despite what people may say about it, it is one of the best things our cars can have in terms of getting rid of the under-hood heat.

When you're driving, the cool air rushes in & collides against your air intake & transmission.

Despite the size of the scoop, more air than you think gets in there & cools things down.

Also, when you have the car parked & off, the heat has somewhere to go instead of being under the hood for a long period of time.

What's not to like about that?

The hood scoop has a purpose but I feel that the wing does not.

The USDM hood scoop has this black piece that you can remove to allow more cooler air in the engine bay as well as allowing heat to get out.

Despite what people may say about it, it is one of the best things our cars can have in terms of getting rid of the under-hood heat.

 

When you're driving, the cool air rushes in & collides against your air intake & transmission.

Despite the size of the scoop, more air than you think gets in there & cools things down.

Also, when you have the car parked & off, the heat has somewhere to go instead of being under the hood for a long period of time.

What's not to like about that?

i can see the heat pour from my scoop on a hot day. sitting in traffic. i am sure it helps the transmission stay cooler as well...especially if your moving. I am planning on putting a non scooped hood on this winter to help keep some heat in. my car runs cold.

2nd gen carbon trunk in progress:

http://sl-i.net/FORUM/viewtopic.php?f=39&t=23440

I checked out his thread and its coming along well but it's got a ways to go. I'm sure in the end he will produce good CF parts but if I'm paying $7-800 I want perfection. It seems like he's got the skills to do it right lets just hope he sticks with it, he hasn't posted any new results in 6 months. I actually have a good friend that owns a shop that makes CF pieces and talking with him it's looks like he would be in the same price range but he's got 15+ years in the business so I know the parts from him would be flawless. He makes a lot of CF parts for the racing industry and a couple of years back he made a complete CF body Lotus. Turned out sick.

Subaru blocked the scoop on non-turbo cars for a reason- it's more aerodynamic and makes the cooling system more efficient. If you are cramming air into the top of the engine bay you are potentially reducing flow through the radiator, plus you have more air going under the car which increases drag and lift.

The air that comes in through the hood scoop go to work as soon as it comes in.

It collides with the air intake & the transmission, cooling the intake & transmission at once (autos need this).

The radiator stays plenty cool during driving events (the coolant temperature while driving remains within the norm.)

Scoop-less hoods are better for aerodynamics but our hood scoops provide too many benefits to be closed off.

I checked out his thread and its coming along well but it's got a ways to go. I'm sure in the end he will produce good CF parts but if I'm paying $7-800 I want perfection. It seems like he's got the skills to do it right lets just hope he sticks with it, he hasn't posted any new results in 6 months. I actually have a good friend that owns a shop that makes CF pieces and talking with him it's looks like he would be in the same price range but he's got 15+ years in the business so I know the parts from him would be flawless. He makes a lot of CF parts for the racing industry and a couple of years back he made a complete CF body Lotus. Turned out sick.

well keep us updated if you work anything like that out! i'd be really happy with a CF hood and trunk, at least.

The air that comes in through the hood scoop go to work as soon as it comes in.

It collides with the air intake & the transmission, cooling the intake & transmission at once (autos need this).

Blowing air across the outside of the case is way less effective than running ATF through the cooler built into the radiator, so you're likely ending up in a net reduction of cooling because less air is going through the actual transmission cooler. The intake air is only in the piping for fractions of a second so having the pipe a couple degrees cooler is basically going to have zero effect on IATs, and with a car driving down the road the underhood temps are basically ambient anyway.

There are literally NO benefits to unblocking the scoop. Only a possible reduction in cooling and economy.

Blowing air across the outside of the case is way less effective than running ATF through the cooler built into the radiator, so you're likely ending up in a net reduction of cooling because less air is going through the actual transmission cooler. The intake air is only in the piping for fractions of a second so having the pipe a couple degrees cooler is basically going to have zero effect on IATs, and with a car driving down the road the underhood temps are basically ambient anyway.

 

There are literally NO benefits to unblocking the scoop. Only a possible reduction in cooling and economy.

Not just outside the transmission case, air is also blown onto the TQ converter, so it aids the cooler in the radiator.

As for the intake piping, plastic is not a very good conductor for heat or the lack of, yet it works okay but a metal CAI will see a significant drop in temps while the car is moving & will be more heat soaked when the car is still.

How is the transmission cooler not going to get air when its far ahead of the hood scoop & the first to collide with the air upon the car's movement?

If anything, it will cool down first with the hood scoop acting as a cooling supplement to the transmission cooler.

The hood scoop is effective because it allows cool air to come in & it allows the ambient heat under the hood to get out effectively.

It works, which it why Subaru invented it for the turbo models but obviously, N/A cars don't have as much heat as the turbo models do.

N/A Subarus still run on the hot side but my car only runs @ 182 degrees tops when I'm driving & my car cools down very quick when I leave it off for long period of time.

It's like this.

Take a bag, run with it, & very quickly, it will "fill up" with air due to the drag/resistance (closed hood scoop).

Then take a bag with a hole on the bottom & do the same thing.

It will not give you anywhere near as much resistance (open hood scoop).

The open hood scoop will give some resistance because it's taking in air but it's actually a functioning unit when the plate is removed.

just because there is a hole in the hood doesnt mean less air is going through the radiator. that is two different entry points, air wont just skip the front of the car and aim for the scoop. the same amount of air is going to go through the radiator regardless of whether theres a hood or not, thats a function of the bumper rams and the cowling around the fans.

i wish i had a fake scoop hood on my wagon, i like the looks. same as the spoiler, mine didnt come with one so im going to add one on. its all for looks tho, i doubt it would ever actually be useful.

The amount of air that comes into the front of the car depends on the difference in pressure between the front of the grill and the inside of the engine bay. Once air comes through the grill and radiator it needs somewhere to go. It hits the engine, fills the bay, goes under the car, and out the wheel wells.

Adding more air into the engine bay via the scoop means you have more pressure in the engine bay and less air coming through the radiator. It's also more air that has to exit under the car and out the wheel wells which results in more drag. You're taking air smoothly flowing over the top of the car, then forcing it through the engine bay and out the bottom. That's not good for aerodynamic efficiency.

Ideally you would want a vent in the hood for air to exit after passing through the radiator, not have a scoop pulling air in.

I was behind a silver Legacy L yesterday and thought about following the guy and asking if he wanted to trade hoods. The pointless scoop has always annoyed me.

The amount of air that comes into the front of the car depends on the difference in pressure between the front of the grill and the inside of the engine bay. Once air comes through the grill and radiator it needs somewhere to go. It hits the engine, fills the bay, goes under the car, and out the wheel wells.

 

Adding more air into the engine bay via the scoop means you have more pressure in the engine bay and less air coming through the radiator. It's also more air that has to exit under the car and out the wheel wells which results in more drag. You're taking air smoothly flowing over the top of the car, then forcing it through the engine bay and out the bottom. That's not good for aerodynamic efficiency.

 

Ideally you would want a vent in the hood for air to exit after passing through the radiator, not have a scoop pulling air in.

 

I was behind a silver Legacy L yesterday and thought about following the guy and asking if he wanted to trade hoods. The pointless scoop has always annoyed me.

It is true that vents are more effective than scoops in the sense that they passively draw in cooler air & allow heat to get out.

The hood scoop is just an aggressive vent that force feeds air & gets rid of heat twice as fast, that's all there is to it.

One would think that the hood scoop & radiator air pressure from driving are equal since the hood scoop & the air passages in the grille & bumper cover are getting air at the exact same velocity.

Also, the hood scoop is in an area that focuses it more on the intake & transmission so if anything, air will be collected & thrust down the sides of the transmission than the engine.

As for air coming out the wheel wells, that is not possible as the plastic shrouds that are in place prevent that from happening.

Air will literally get under the car as you have stated but most of us are either dropping the cars or lifting them, so the small detriment that the hood scoop causes is either extremely diminished or simply not cared about.

On the subject of the hood scoop & the front of the car, if anything, they will both get air but that doesn't cause the radiator to cool less efficiently.

Hood scoops in general, covered or uncovered, are not aerodynamically good for the car but why not utilize the hood scoop since it's already there?

It does it's function very well & the drag that it creates on the car isn't anywhere near as sufficient as say, the rear wing or even an aftermarket one.

By removing the wing & hood scoop, you still wouldn't be able to generate what it would take to make the car perform significantly better & the heat generated by the engine would stay trapped there for hours without the hood scoop, keeping the intake piping heated, which is what we don't want.

The cooler the intake air coming into the intake manifold, the better it will be for power/tq & for fuel economy.

I thought I explained it clearly, but I guess not.

Think of the engine bay as a box. Air comes in through a hole in the front and out through a hole in the back. If we cut an extra hole in the front of the box, we need an extra hole in the back of the box to keep things even. Without it, the pressure in that box increases and slows down the air coming in. If you slow down the air coming into the engine bay, you slow down the air coming through the radiator and reduce the cooling ability.

But since I can't seem to explain this logically why don't we look at the real world. No production car anywhere has a hood scoop that is not feeding a cooler. If hood scoops "got rid of heat twice as fast" then you would think every car in the world would have one. But they don't. Our cars have scoops that are just there for looks and Subaru blocked them off for a reason. If it actually improved cooling don't you think they would be open?

Now look at production based race cars. No scoops there either- just vents. Prodrive fought with Subaru for years over the scoop because it was bad for cooling and aerodynamics but it was part of the "brand image" and the racing budget comes from marketing. So they ended up sealing the scoop to the air intake. They also ducted the radiator and intercooler to prevent any unwanted air from entering the engine bay.