Hey guys I have a 93 hb .... I have been doing research trying to figure out what gains you get from a duckbill spoiler heres what I have figured out. Please feel free to correct me if I am off.

When your car is in motion air passes over it creating turbulance behind the car a sort of vacume behind the car that creates drag.

With a duckbill spoiler the air passing over your car is directed up and away from your car preventing the swirling turbulance thus less drag ..........


Am I correct ? if I am not could you please clear it up for me ?

 

that may be true for speeds in excess of 100mph, but otherwise, it's just for show

 

From what i have read spoilers (even ricer wings) start to become affective at less then 30 mph ... I could be wrong though ...

 

From what Porsche engineers say about their own cars' wings and other wings, they're only effective at 120+ mph.

 

thats in the case of down force. but for the turbulence thing he's right. it worksat pretty much any reasonable speed.

 

did a little more research and found this tonight

"Results of independent tests conducted using a 1969 Camaro Z/28 clearly demonstrate the practical value of the optional spoiler equipment. The testing was conducted by the editors of CAR LIFE magazine and the results appear in the June 1969 issue.
In order to standardize the tests, a single Camaro Z/28 was evaluated both with and without the factory spoiler equipment installed. This testing method eliminated any vehicle/chassis variations that may occur between two different vehicles which can "factor in" affecting the validity of test results.
Parameters measured were lift and downforce. The two most important aerodynamic factors that affect traction and handling at speed. Speed intervals of at 65, 85, and 115 mph were chosen as a practical range of test points for analysis and comparison. The 65 mph mark representing a typical highway speed, 85 as the intermediate passing or top crusing speed, and 115 as an average race speed on medium and short road race courses. "

"CONCLUSION...

The spoilers produced the desirable effects of increased traction along with a slight understeer condition. In controlling the lift of the nose so well, there was an increase in stability that a sensitive driver is able to feel even at moderate speeds.
In referring to the graph, It should be noted that the effectiveness of the spoiler equipment is proportional to vehicle speed. The faster you go the more effect the equipment has. The best part is it looks as good as it works!
"



If you look close at the graph you can see the downforce effect is taking effect at actuly less the 30 mph ...

 

you show us a test of a 30+ year old camaro to prove ur point? . . .. . . ..

 

well just look at the ITR wing
its there for function not fashion

 

this is true....but 99% of those who have the duck bill is for appearance modifications.....not for performance...

i would have one cause i road race and do reach speeds well over 130 mphs and it would help

 

Yes .. because its based on physics .. and that hasent changed in the last ohh EVER !!!!

 

if a wing is only functional beyond 100mph or 120 as i think someone stated then why does the wing come up on a porsche (sp?) at low cruising speed? by low cruising speed i mean in the area of 40mph. i saw this on an early 90's model on the way to work this morning. They guy never got it over 45 but at every light we'd stop at he would pull a little past me and i could see the wing go down.


[Modified by thinkbrianthink v.1, 12:18 PM 1/7/2003]

 

Since when has gravity, wind resistance, and the theories of downforce changed? They haven't. His example is relevant since the same formulas are still in use to figure out downforce, drag, etc. Think before you start to flame.

Chris

 

tight!

 

From what I've learned, most aluminum wings help create more downforce, and fiberglass wings are for looks. Personally, I wouldn't have either on my car. I've read that they only affect downforce at speeds upward of 80 mph. Unless you're going faster than that, they don't create enough downforce to make a difference.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CivicDX95 &raquo;</TD></TR><TR><TD CLASS="quote">From what I've learned, most aluminum wings help create more downforce, and fiberglass wings are for looks. </TD></TR></TABLE>

I fail to see how wing material affects performance.

-Scott

 

Spoilers can help, but I would have to agree that most are show. Especially most OEM ones.

Not saying your wrong, but if the Porsche one is only good above 120, why would they "open" at 55-60mph? can't remember the exact speed it opens at.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EKDreamin &raquo;</TD></TR><TR><TD CLASS="quote">

I fail to see how wing material affects performance.

-Scott</TD></TR></TABLE>
The material itself doesn't affect the preformance. It's how they're designed.

 

You might want to look into the reasons/technology that went into the recall and addition of spoilers on Audi TT's. I'm not gonna go too in depth about it, but after having several TT's flip on the autobahn as a result of them being so aerodynamic that a pocket of air was building under the rear end of the car causing it to lift and the car to lose control. Might possibly be one of the reasons for a duckbill, to prevent the moving air from coming off the roof down the hatch and underneath the car. Considering duckbills come straight out, not angled up or down like a trunk spoiler, I doubt you will find that they are designed to increase traction on the rear end.

-Scott

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Stryker908 &raquo;</TD></TR><TR><TD CLASS="quote"> &lt;BLOCKQUOTE&gt;quote:&lt;HR&gt;you show us a test of a 30+ year old camaro to prove ur point? . . .. . . .. &lt;HR&gt;&lt;/BLOCKQUOTE&gt;

Yes .. because its based on physics .. and that hasent changed in the last ohh EVER !!!! </TD></TR></TABLE>
own3d!

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CivicDX95 &raquo;</TD></TR><TR><TD CLASS="quote">
The material itself doesn't affect the preformance. It's how they're designed.</TD></TR></TABLE>
own3d!

The wings at the back create downforce, much the same way how aircrafts fly (Bernoulli's theory). Its just positioned upside down so instead of lifting the car, it pushes the car to the ground as airspeed increases, due to the "aerofoil" design.

I think the point of this discussion is how the spoilers reduce drag by deflecting air from the rear of the vehicle thus minimizing turbulence. This is effective at even less than 35mph. Creating downforce is another topic.

 

You guys basically have it right, but remember. Wings and Spoilers are DIFFERENT.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RotiEatter &raquo;</TD></TR><TR><TD CLASS="quote">

Not saying your wrong, but if the Porsche one is only good above 120, why would they "open" at 55-60mph? can't remember the exact speed it opens at. </TD></TR></TABLE>

its a selling feature?

 

Here I did a search and found this, I'm sure they know more about this than I do and many others in this forum
[URL]
http://www.grc.nasa.gov/WWW/K-12/air....html[/URL]

Maybe it clears it up some.
With those two theories, it would show the duckbill may have some down force(probably very little) and can verify the downforce. I am sure it has some sort of effect on aerodynamics in some way or form.

Peace,
Steve

 

http://www.grc.nasa.gov/WWW/K-....html

 

[OffTopic] How come your hatch is running mid/high 15's with a b16a? is it an
SiR ll? [/OffTopic]

 

your point about it affecting the camero is relavent but the graph shows, if im reading it right, that as speed increases the front lifts as the back lowers, while this would be good for the rwd camero wouldnt it be a not so good thing for the fwd cars we all have here? becuase correct me if im wrong would you want more downforce in the front if your front wheels are driving the car?