Welcome to the North American Subaru Impreza Owners Club Sunday February 1, 2015
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Subaru Models > Impreza Forum

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 08-17-2001, 04:15 AM   #1
fungo phil
Guest
 
Member#:
Question What is the function of a "waist spoiler"

A couple of weeks ago there was a thread concerning the installation of a waist spoiler. The last post in the thread asked what the functionality of the spoiler was and the question was never responded to. Other than a place to set your beer during a tailgate party what is the fuctionality of a waist spoiler and how does it work, especially when it has a roof spoiler just above it? Anybody?
* Registered users of the site do not see these ads.
  Reply With Quote
Old 08-17-2001, 09:34 AM   #2
RidinLow
Scooby Guru
 
Member#: 329
Join Date: Sep 1999
Chapter/Region: Tri-State
Location: NJ
Vehicle:
1995 325i
Arctic Gray

Default

It looks cool, that's about it. A spoiler has to be in an area where air actually hits it for it to do something.
RidinLow is offline   Reply With Quote
Old 08-17-2001, 12:39 PM   #3
scoobagenie
Scooby Newbie
 
Member#: 5283
Join Date: Mar 2001
Location: somewhere probably sucking on mentos
Vehicle:
02 wrx wagon
black

Default

agree with ridinlow. it sure does looks pretty though
scoobagenie is offline   Reply With Quote
Old 08-17-2001, 12:49 PM   #4
SRI Performance
Vendor
 
Member#: 2448
Join Date: Sep 2000
Location: brunswick, Ohio 44212
Vehicle:
1997 subaru
green and yellow

Default

You know i would buy one if it wasn't so much money. I have been waiting for someone to sell one,
But i think subaru selld them for what...500 bux. I paid that much for a SYMS rear wing
Chris
They do look bad-ass though and it totally accent the wagons.
SRIPerformance.com
SRI Performance is offline   Reply With Quote
Old 08-17-2001, 01:41 PM   #5
RRinDC
Scooby Newbie
 
Member#: 204
Join Date: Aug 1999
Location: DC Suburbs
Vehicle:
1998 Impreza OBS
Glacier White/Slate

Default

At high speeds (racetrack speeds, or "GT3 speeds" for some people) a waist spoiler would presumably provide some aerodynamic benefit (downforce, stability, etc.) You shouldn't be reaching those speeds on public roads.

Subaru of America would probably say (like they said about the hoodscoop on last-gen 2.5RS and OBS): "Sure it's functional. It's function is stylistic."

I think the function of a waist spoiler is to waste your money.
RRinDC is offline   Reply With Quote
Old 08-17-2001, 01:51 PM   #6
jeffg
Scooby Guru
 
Member#: 2958
Join Date: Nov 2000
Chapter/Region: NWIC
Vehicle:
2001 WRX (GC8)

Default

The first problem you all have is spelling..... it is a WASTE spoiler, not a Waist spoiler. With that spelling you can see its purpose.


jk

Jeff
jeffg is offline   Reply With Quote
Old 08-17-2001, 02:52 PM   #7
Jon [in CT]
*** Banned ***
 
Member#: 2992
Join Date: Nov 2000
Chapter/Region: NESIC
Location: Connecticut, USA
Vehicle:
02 WRX Sedan
Silver

Default

It obviously serves the same purpose as the 2.5 RS hood scoop.
Jon [in CT] is offline   Reply With Quote
Old 08-17-2001, 03:01 PM   #8
fungo phil
Guest
 
Member#:
Post

Right, it is a "WASTE" your $$$ spoiler. And at race track speeds that thing would be sitting in an aerodynamic vacuum in the slip stream of the wagon, totally useless except for that occasional beer can.
  Reply With Quote
Old 08-17-2001, 04:10 PM   #9
Travis R
Scooby Specialist
 
Member#: 153
Join Date: Aug 1999
Location: Austin, TX
Vehicle:
'07 Mazda CX-7, '91
BMW 535i & '06 Ninja 650R

Default

I don't usually give in to the aesthetic mods (side skirts, lip spoilers, etc), but this is the one "visual" option that will have on my wagon. I can't rationaly explain why I like it. I just looks awesome.
You're right though, probably no aerodynamic difference.
Travis R is offline   Reply With Quote
Old 08-17-2001, 04:46 PM   #10
gtguy
Scooby Guru
 
Member#: 2184
Join Date: Aug 2000
Location: Highland Park, Ill., USA
Vehicle:
2005 Legacy GT wagon
Platinum Silver Metallic

Default

I really like it with the Subaru wagon body kit, but not alone. And being fond of stealth, though I was blown away by the wagon pix from a Euro auto show, in real life, I love the looks of my wagon.

I don't think that the waist spoiler has any benefits aerodynamically, though when you imagine air flow over the wagon, it might have some benefit at triple-digit velocities.

Kevin
gtguy is offline   Reply With Quote
Old 08-17-2001, 05:29 PM   #11
5252
Guest
 
Member#:
Default I can't take the credit for this but..

... Someone else on another forum mentioned how small the Audi TT spoiler was, but it was just enough to solve their light tail problem. I thought it was an exellent observation.
An aerodynamic mod does not have to grab the air and strangle it or wrestle it to do some good. Even pushing down on the trunk lid which in turn pushes down on the trunk lid stops ( little rubber feet) actually effects the car. sometimes this is all it takes to clear up some light tail issues. on the other hand my MY98 coupe wing removed added ten mph top end.
I always liked the look of the wagon with wings and w/out rack. someday I will gut my coupe and put it all in a wagon.
  Reply With Quote
Old 08-17-2001, 06:36 PM   #12
Eric SS
Sooby Guru
 
Member#: 1914
Join Date: Jul 2000
Chapter/Region: SWIC
Location: 2013 335i, 2011 G37 coupe
Vehicle:
2000 2.5RS w/ EJ22T
swap and N20. gone. : (

Default

Actually it does have some functionality. It can actually help keep your rear windshield clean and easier to see through.

Eric
Eric SS is offline   Reply With Quote
Old 08-17-2001, 07:48 PM   #13
stever
Scooby Specialist
 
Member#: 1512
Join Date: May 2000
Location: Costa Mesa, land of white fire hydrants
Vehicle:
99 2.5RS
Rally Blue and Black

Default

I don't see what the big deal is. It's perfectly functional ... knock out the windshield and the back window it'll work fine.

-Steve

Stephen.Ramm@aerosim-research.com
stever is offline   Reply With Quote
Old 08-18-2001, 04:12 AM   #14
subysouth
Scooby Guru
 
Member#: 5039
Join Date: Mar 2001
Chapter/Region: South East
Location: Ocean Springs, MS
Vehicle:
2007 Outback XT
Grey 5-speed

Default What???

Someone post a pic of this relleged waist spoiler.
subysouth is offline   Reply With Quote
Old 08-18-2001, 12:46 PM   #15
Zerly
Scooby Newbie
 
Member#: 2691
Join Date: Oct 2000
Location: WA
Vehicle:
2001 Impreza RS
Silverthorn Metallic

Question

Curious to see what a waste spoiler looks. Pics please.
Zerly is offline   Reply With Quote
Old 08-18-2001, 03:59 PM   #16
Jon [in CT]
*** Banned ***
 
Member#: 2992
Join Date: Nov 2000
Chapter/Region: NESIC
Location: Connecticut, USA
Vehicle:
02 WRX Sedan
Silver

Default

It's the spoiler just BELOW the rear window:
Jon [in CT] is offline   Reply With Quote
Old 08-18-2001, 04:09 PM   #17
jagcars26
Scooby Specialist
 
Member#: 2394
Join Date: Sep 2000
Chapter/Region: MAIC
Location: Bel Air Md.
Vehicle:
2005 Legacy GT wagon
2009 Forester X

Default

$500 bucks fr that???? looks good but not 500 worth.
my two cents
Rudy
jagcars26 is offline   Reply With Quote
Old 08-18-2001, 09:56 PM   #18
Zombie
Scooby Newbie
 
Member#: 7076
Join Date: May 2001
Location: Newton, NC
Vehicle:
2000 Outback Sport
Silverthorn/Titanium

Default

it covers up the only ugly piece of sheet metal on the wagon

zombie
Zombie is offline   Reply With Quote
Old 08-19-2001, 01:03 AM   #19
Porter
NASIOC Supporter
 
Member#: 486
Join Date: Nov 1999
Chapter/Region: MAIC
Location: Roanoke, VA
Vehicle:
2004 Forester XT
bug spattered

Default

You are wrong about the waist spoiler on the WRX wagon. I find it entertaining how snide everyone becomes when they make idiotic assumptions based on ZERO scientific fact. No offense toward any of you personally, just pointing it out.

2 points:

First, the Impreza "wagon" shape is actually more of a euro "5 door" design, meaning a 4 door hatchback. Traditionally, wagons had a very vertical rear surface, but that is not even remotely true on this vehicle. There is a significant slant to the rear window and a pronounced rear decklid where the waist spoiler mounts. There is far more airflow here than you think. As the entire shape of the vehicle is very winglike, any inverted wing surfaces are quite advantageous in reducing lift.

Second, as air passes over the top of the vehicle, it has a tendency to spin over the trailing edge of the roof and create a vortex against the back window, a low pressure area that induces a significant amount of drag on the vehicle at even mild speeds. The location and design of the roof spoiler plays on this tendency, the large opening between the roof and the wing surface allows passing air to create a low pressure area against the bottom of the wing as it begins to rotate downward. If the wing were contiguous with the roof, it would only increase the magnitude of the vortices and provide very little downforce. The waist spoiler helps to foil the air once it has begun to spin downward, and prevents it from "pooling" at the back of the car in a low pressure zone. The new bridge type waist spoiler for the new body style wagon also extends slightly on either side of the body, helping to draw air in a more controlled manner around the back of the car and across the wing surface.

I think it would be very interesting to see the air behavior around the back of the wagon in a wind tunnel. I remember reading that when engineers added a very slight lip to the edge of the trunklid of the Saab 9-5, it reduced overall drag by almost 15%, purely by reducing the tendency of the air to vortex. The difference was less than 1/4 inch. Fluid dynamics are an amazingly powerful thing, it dissapoints me that so many people on the board try to discount them as only significant at extreme speeds. Aerodynamics plays a role at ANY speed, and a much larger one than people give it credit for. It can drastically affect the handling and performance of a vehicle, even at modest speeds.


-Porter
Porter is offline   Reply With Quote
Old 08-19-2001, 01:58 AM   #20
trinidriver
Scooby Newbie
 
Member#: 8121
Join Date: Jul 2001
Location: Connecticut
Vehicle:
2002 WRX Wagon
WR Blue

Default

How about the spoiler that replaces the OEM one but sits a few inches taller than the roof? What do you guys think of that one? Who sells them?
trinidriver is offline   Reply With Quote
Old 08-19-2001, 10:14 AM   #21
T-WRX
Scooby Specialist
 
Member#: 2468
Join Date: Sep 2000
Chapter/Region: South East
Location: JAX
Vehicle:
08 RS4
05 STi - Gone

Default

I'd be interested to see if anyone has driven in the rain with a waist spoiler. I remember seeing pictures of perfectly still beads of water on the 2.5RS coupe's wing, while the car was at speed.
T-WRX is offline   Reply With Quote
Old 08-19-2001, 10:48 AM   #22
tahrndt
Scooby Specialist
 
Member#: 1315
Join Date: Apr 2000
Location: Minneapolis, MN. U.S.A.
Default

This is easy enough to check if it is functional or just for Fun. Someone that has one tape a several rows of small pieces of yarn on the top of the spoiler. Have someone sitting in the back or video tape it. Bring the car up to speed and observe the yarn. If they just sit there and dont fly around, Then it is just for looks and Porters theory might not be true. If they are swirling and flapping around then it is smoothing out the air flow on the bottom edge, actually performing a function.
I do not think that any air will be acting upon it personally. IIRC a rear window area of an auto that is around 23 degrees or less, will allow the air to flow over the surface almost sticking to it. Angles greater than 23 will cause the air to flow over and cause a vacuum in its void. Imagine a semi truck here folks.
TIm
tahrndt is offline   Reply With Quote
Old 08-19-2001, 02:11 PM   #23
FuJi K
Scooby Guru
 
Member#: 3687
Join Date: Jan 2001
Chapter/Region: MWSOC
Location: St. Paul, MN
Vehicle:
MY99 GF4 JDM 6spd
NF Performance

Default

here's a effect...............

it makes your REX look faster
FuJi K is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
What is the Function of Fender Braces? Sti_Boxer Brakes, Steering & Suspension 8 07-15-2009 03:12 PM
what is the function of the "scroll lock" key? alacrity024 Off-Topic 12 05-11-2006 12:38 PM
what is the name of the machene gun that sticks out of the side of a bomber D-I-Z-Z-L-E Off-Topic 29 10-25-2004 08:30 PM
what is the name of the time machine that is on the back of the car crowbar Off-Topic 17 10-24-2004 09:30 PM
what is the name of the dragstrip that is north of Waco? AWDball Texas Impreza Club Forum -- TXIC 9 12-27-2002 08:06 PM


All times are GMT -4. The time now is 09:18 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.