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-   -   Bug Deflector Air-Flow (https://www.seccs.org/forums/showthread.php?t=3794)

tysonK 2005-10-30 11:27 AM

Bug Deflector Air-Flow
 
1 Attachment(s)
I wanted to interupt more damage to the front of my hood so I was thinking about purchasing a front bug deflector.

It says for non-turbo application, on the subaru instructions. I guess it shunts to much air above the hood scoop?

Clear bra is the only real option?

Nick Koan 2005-10-30 11:43 AM

Yeah, that and even the leather bra redirects too much air. I think clear bra is your only option.

JC 2005-10-30 11:58 AM

Quote:

Originally Posted by nKoan
even the leather bra redirects too much air.

They make a WRX specific one.

sperry 2005-10-30 12:04 PM

Quote:

Originally Posted by JC
They make a WRX specific one.

Actually, I think they used to sell the RS one for the WRX, then changed their mind and labeled it as "RS/TS Only"... unless there's a new one out for the bug-eyes.

Which reminds me, I've got a bug-eye bra purchased from back when they were considered "okay" for the WRX. I'll sell it to ya Tyson if you're willing to "risk" the airflow issue... which I don't think is a hoodscoop flow issue, I believe it's a snorkus flow issue under the hood.

tysonK 2005-10-30 12:08 PM

Quote:

Originally Posted by sperry
Actually, I think they used to sell the RS one for the WRX, then changed their mind and labeled it as "RS/TS Only"... unless there's a new one out for the bug-eyes.

Which reminds me, I've got a bug-eye bra purchased from back when they were considered "okay" for the WRX. I'll sell it to ya Tyson if you're willing to "risk" the airflow issue... which I don't think is a hoodscoop flow issue, I believe it's a snorkus flow issue under the hood.

It might look armour on my black car. I can give it a try.

tysonK 2005-10-30 12:09 PM

1 Attachment(s)
this guys sports one.

Nick Koan 2005-10-30 12:35 PM

True, but I've seen a lot of people do stupid things with their WRXs.

Nice highway BTW.

cody 2005-10-30 01:04 PM

What you need is a shield that doubles as a vortex generator to focus more air into the scoop. Now that'd be pimp.

sperry 2005-10-30 01:29 PM

Quote:

Originally Posted by cody
What you need is a shield that doubles as a vortex generator to focus more air into the scoop. Now that'd be pimp.

So, basically you want a deflector that actually *increases* the number of bugs that hit the car. Interesting! :lol:

cody 2005-10-30 01:32 PM

So you'd have a few more bugs hitting the scoop and the windshield...I'm not scared.

sperry 2005-10-30 01:38 PM

Quote:

Originally Posted by cody
So you'd have a few more bugs hitting the scoop and the windshield...I'm not scared.

It's not much of a "deflector" if it actually increases debris into the car, which is exactly what Tyson's trying to prevent.

Quote:

Originally Posted by tysonK
I wanted to interupt more damage to the front of my hood so I was thinking about purchasing a front bug deflector.

If you really want more air into the hood scoop, just get a bigger hood scoop.

cody 2005-10-30 03:14 PM

How is a piece of material on the hood going to increase debris reaching the car? :confused: The vortex generator/hood protector would point more air into the hood scoop and protect the hood from damage. A piece of debris that reached the hood wouldn't be any more dangerous or common. It's not going to suck junk off the road and throw it at the car.

JC 2005-10-30 03:26 PM

Quote:

Originally Posted by sperry
Actually, I think they used to sell the RS one for the WRX, then changed their mind and labeled it as "RS/TS Only"... unless there's a new one out for the bug-eyes.

Which reminds me, I've got a bug-eye bra purchased from back when they were considered "okay" for the WRX. I'll sell it to ya Tyson if you're willing to "risk" the airflow issue... which I don't think is a hoodscoop flow issue, I believe it's a snorkus flow issue under the hood.

Your right, I was thinking of the deflector.

https://www.subarugenuineparts.com/p...roducts_id=650

sperry 2005-10-30 04:16 PM

Quote:

Originally Posted by cody
How is a piece of material on the hood going to increase debris reaching the car? :confused: The vortex generator/hood protector would point more air into the hood scoop and protect the hood from damage. A piece of debris that reached the hood wouldn't be any more dangerous or common. It's not going to suck junk off the road and throw it at the car.

I'm not a aerodynamicist so I'll defer to JC on the details, but the way a bug deflector works is by spoiling air at the leading edge of the hood so bugs are deflected by the airflow up and away from the hood/windshield.

If you're attempting to use the same principle to direct more air at the hoodscoop, you're going to also be directing anything in that air at the scoop, and therefore the windshield behind it. I.e. bugs and the like that would normally by pushed aside by the shape of the hood are now being directed at the car.

Not only would such a "vortex generator" probably work worse than a properly designed hood scoop, it would probably concentrate bugs into the scoop, and on the windshield, not to mention the possible effects during wet conditions... personally I'd rather have as close to laminar flow over my windshield, rather than a swirling mess of rain/snow.

...but again, I've got no background in aerodynamics aside from a general understanding, so I'll differ to the people that know more about these things like JC and AtomicLabMonkey.

JC 2005-10-30 04:30 PM

If you want more airlfow into your hood scoop, buy a bigger one. If you want less bugs on your car, get a daily driver.

Scott got it basically right, though I have no idea why the word vortex generator is being thrown around. On a related note, I have no idea about the new deflectors but the old style ones (straight vertical) would noticably decrease mileage or so I've been told by people who had them. I'm sure the new ones lessen the effect but you are still adding drag to your car for the sake of a cleaner windshield.

tysonK 2005-10-30 05:02 PM

Quote:

Originally Posted by JC
If you want more airlfow into your hood scoop, buy a bigger one. If you want less bugs on your car, get a daily driver.

Scott got it basically right, though I have no idea why the word vortex generator is being thrown around. On a related note, I have no idea about the new deflectors but the old style ones (straight vertical) would noticably decrease mileage or so I've been told by people who had them. I'm sure the new ones lessen the effect but you are still adding drag to your car for the sake of a cleaner windshield.

Well the paramount reason I wanted the get the deflector was to act as a leading edge shield for my hood. I guess I could just get a little clear bra strip. I'm worried that with another winter or so I might be having to repaint it soon or get a new hood, it really bothers me. My hood has the most chips right where the bug deflector would be.

I don't care about the bugs hitting my windshield I wash it everytime I get home.

cody 2005-10-31 08:33 AM

Quote:

Originally Posted by sperry
I'm not a aerodynamicist so I'll defer to JC on the details, but the way a bug deflector works is by spoiling air at the leading edge of the hood so bugs are deflected by the airflow up and away from the hood/windshield.

If you're attempting to use the same principle to direct more air at the hoodscoop, you're going to also be directing anything in that air at the scoop, and therefore the windshield behind it. I.e. bugs and the like that would normally by pushed aside by the shape of the hood are now being directed at the car.

Not only would such a "vortex generator" probably work worse than a properly designed hood scoop, it would probably concentrate bugs into the scoop, and on the windshield, not to mention the possible effects during wet conditions... personally I'd rather have as close to laminar flow over my windshield, rather than a swirling mess of rain/snow.

...but again, I've got no background in aerodynamics aside from a general understanding, so I'll differ to the people that know more about these things like JC and AtomicLabMonkey.

I agree with some of what your saying, but keep in mind that the "bug deflector" wouldn't work on a WRX retaing the TMIC. I'm just saying if you have a rock guard on the front of your hoood to protect it from chips, why not design it so that it points more or the same amount of air into the scoop instead of hampering the flow. Then you can have your cake and eat it too.

Sure, more bugs are going to hit your car than if you were running a true bug deflector that pitches air and debris over your car, but that's not an option on TMIC car. The amount of bugs/debris that hit your car with the vortex generator hood protector thingy would be similar to without, I'm guessing.

JC, I got the word "vortex generator" because the EVO MR has one on the rear edge of the roof to put more force on the rear wing.

Maybe it is a dumb idea. I mean if you've got a couple of aerodynamicists on your side, I'll just shut up.

Nick Koan 2005-10-31 09:10 AM

I think JC means you could direct air at the hoodscoop without generating any vorticies IF that is what you really wanted to do.

But, again, if rock chips are all you are trying to prevent, then a clearbra/rockblocker type film would be the best answer.

cody 2005-10-31 09:16 AM

Yah that's what I have, I'm just playing devil's advocate. :devil:

JC 2005-10-31 09:55 AM

Quote:

Originally Posted by cody
I agree with some of what your saying, but keep in mind that the "bug deflector" wouldn't work on a WRX retaing the TMIC. I'm just saying if you have a rock guard on the front of your hoood to protect it from chips, why not design it so that it points more or the same amount of air into the scoop instead of hampering the flow. Then you can have your cake and eat it too.

Sure, more bugs are going to hit your car than if you were running a true bug deflector that pitches air and debris over your car, but that's not an option on TMIC car. The amount of bugs/debris that hit your car with the vortex generator hood protector thingy would be similar to without, I'm guessing.

JC, I got the word "vortex generator" because the EVO MR has one on the rear edge of the roof to put more force on the rear wing.

Maybe it is a dumb idea. I mean if you've got a couple of aerodynamicists on your side, I'll just shut up.

Because it's no longer a bug deflector is the simple answer. The point of a bug deflector is to deflect bugs over your windshield. It you changed it that it directed them AT your windshield it would no longer serve it's primary purpose. I'm not sure how you'd go about directing air at the scoop anyway but I can assure you it's much more effective to just get a larger scoop. I assumed that's where you got vortex generator from but it doesn't relate to bug deflectors. :p

JC

cody 2005-10-31 10:02 AM

Again, forget about deflecting bugs on a car with a TMIC. The original poster wants to protect his hood. My idea would theoretically serve that purpose without hampering flow to the hood scoop.

JC 2005-11-01 08:36 AM

Quote:

Originally Posted by cody
Again, forget about deflecting bugs on a car with a TMIC. The original poster wants to protect his hood. My idea would theoretically serve that purpose without hampering flow to the hood scoop.

The simple answer is it's not practical.

cody 2005-11-01 08:42 AM

You mean because of the necessary R&D?

Nick Koan 2005-11-01 08:59 AM

Quote:

Originally Posted by cody
You mean because of the necessary R&D?

The compromises. There are too many compromises to make the whole idea not practical.

sperry 2005-11-01 09:42 AM

Quote:

Originally Posted by nKoan
The compromises. There are too many compromises to make the whole idea not practical.

Plus, clearbra's already been invented.

cody 2005-11-01 09:44 AM

Everybody thought Newton was crazy once. :P

sperry 2005-11-01 09:48 AM

Quote:

Originally Posted by cody
Everybody thought Newton was crazy once. :P

:lol: Yeah, but he came up with something new.

Quote:

Originally Posted by Cody
Again, forget about deflecting bugs on a car with a TMIC. The original poster wants to protect his hood. My idea would theoretically serve that purpose without hampering flow to the hood scoop.

This has already be invented by 3M. :P

Nick Koan 2005-11-01 09:49 AM

Quote:

Originally Posted by cody
Everybody thought Newton was crazy once. :P

Its not that the idea is crazy....

Nick Koan 2005-11-01 06:29 PM

Alright. Thread cleaned up a little.

Feel free to keep nonsensically-arguing in the other thread.

MattR 2005-11-01 09:17 PM

I have clearbra on all my vehicles, I'm better than you are.

cody 2005-11-01 09:36 PM

I can't believe some of you don't have clearbra on your Subarus, expecially if you drive in the winter up here. The paint chips when you look at it wrong.

ScottyS 2005-11-02 10:37 AM

Quote:

Originally Posted by cody
I can't believe some of you don't have clearbra on your Subarus, expecially if you drive in the winter up here. The paint chips when you look at it wrong.


My front-end paint chips came free of charge...

tysonK 2005-11-02 03:00 PM

Quote:

Originally Posted by cody
I can't believe some of you don't have clearbra on your Subarus, expecially if you drive in the winter up here. The paint chips when you look at it wrong.

I didn't know about it until after I bought my car, I would have done my entire car.

cody 2005-11-02 03:02 PM

Yah, a clearbra does seem like a bandaid to the real problem (litterally). I've always wondered if it would be feasible to have the entire car clearcoated or somthing right after getting it.

Nick Koan 2005-11-02 03:04 PM

Line-x the whole thing.

M3n2c3 2005-11-03 07:32 AM

I'll likely replace my hood eventually anyway. . . and it's too late for the rest of my front end. It came stock with pinprick paint chips in the bumper :P

Vwflat4driver 2005-11-04 07:26 PM

damn semi trucks anyways. rock chip galore and one chipped windshield and she's only a couple months old!! god have mercy on nevada! get rid of granite contruction!!!...

Kevin M 2005-11-04 08:02 PM

Seriously... I wouldn't pay those guys to pave a driveway. :mad:

AtomicLabMonkey 2005-11-05 05:17 PM

Quote:

Originally Posted by cody
Everybody thought Newton was crazy once. :P

Did you really just compare yourself to Isaac Newton in this conversation?

Wow.

cody 2005-11-05 07:42 PM

Hi Labmonkey. Yah, but that was a few days ago. Today I feel more like Socrates. Regardless, please try to stay on topic. This is the serious thread. ;)

TIA,
Cody

AtomicLabMonkey 2005-11-05 10:19 PM

Quote:

Originally Posted by cody
Yah, but that was a few days ago. Today I feel more like Socrates. Regardless, please try to stay on topic.

Sorry, a few days ago I was busy actually being an engineer.


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