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At what point would the rear wagon roof spoiler be effective and would it be advisable to have it?
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Psychwarlord)

Spoiler's create downforce. On the track it will help push the rear wheels into the ground, get more traction and providing better handling in turns, but in a straight line, it lowers the vehicle's top speed.
 

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Re: Does V70R rear roof spoiler make a difference in handling? (C70drvr)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>C70drvr</b> »</i></TD></TR><TR><TD CLASS="quote"> but in a straight line, it lowers the vehicle's top speed.</TD></TR></TABLE><p>Not always true. The V's rear aero device (I'll not use term spoiler) is virtually flat. It really doesn't increase the actual frontal area. In some causes, aero devices may actually lower the Cd, and thus can reduce the <u>effective</u> frontal area. The small lip on the bottom of the front chin valance is an example of the latter.<p>
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Psychwarlord)

My spoiler adds about 10 MPH to the top speed and cuts two seconds off my 0-60 times. Oh yea, and it gets the girls too. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/wink.gif" BORDER="0">
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Dashdog)

It does delfect rain, etc. when the car is in forward motion.<p>The rear window stays cleaner. Not really a performance feature... <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/rolleyes.gif" BORDER="0">
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Psychwarlord)

As Jim stated, it is virtually flat and with no contour, it does little for high-speed stability. The S60R spoiler is supposedly supposed to add 20% downforce I believe (could be wrong about that though) at well over 100MPH.
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Dashdog)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Dashdog</b> »</i></TD></TR><TR><TD CLASS="quote">My spoiler adds about 10 MPH to the top speed and cuts two seconds off my 0-60 times. Oh yea, and it gets the girls too. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/wink.gif" BORDER="0"> </TD></TR></TABLE><p>Only 10? I get 20mph top speed and tremendous grip in the corners, at least an extra 35 mph on the off-ramps...<p> <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/biggrin.gif" BORDER="0"> <p>
 

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Re: Does V70R rear roof spoiler make a difference in handling? (FastWgn)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>FastWgn</b> »</i></TD></TR><TR><TD CLASS="quote"><p>Only 10? I get 20mph top speed and tremendous grip in the corners, at least an extra 35 mph on the off-ramps...<p> <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/biggrin.gif" BORDER="0"> </TD></TR></TABLE><p>Yea, I heard the spoiler is a little quicker with the red paint.
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Vipergtsz3)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Vipergtsz3</b> »</i></TD></TR><TR><TD CLASS="quote">As Jim stated, it is virtually flat and with no contour, it does little for high-speed stability. </TD></TR></TABLE><p>Not true. I always drove my V70R without the spoiler. Did 174 mph with the car and it was horrible. Added the spoiler and things became much better.
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Johann)

The spoiler is flat on top but actually curved on the bottom, thus making it a small upside-down airfoil. I'm sure it creates a small amount of negative lift, but due to its size I doubt it's very effective below about 100 mph. Of course like anything sticking out into the wind, it creates drag as well.
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Dashdog)

<br>Isn't also the case that since the V is vertical in the back, there is a significant lesser pressure zone behind the car and funneling some of the overpressure from above the car into that low pressure zone actually decreases the low pressure and hence makes the car more stable?<br>That is, you decrease the size and power of the venturi flows?<p>This is of course also why the rear widnow gets less dirty, the dirt is not "sucked up" as high.<p>Any fluid dynamics engineers on this list? <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/smile.gif" BORDER="0">
 

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Re: Does V70R rear roof spoiler make a difference in handling? (FastWgn)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>FastWgn</b> »</i></TD></TR><TR><TD CLASS="quote"><br>Isn't also the case that since the V is vertical in the back, there is a significant lesser pressure zone behind the car and funneling some of the overpressure from above the car into that low pressure zone actually decreases the low pressure and hence makes the car more stable?<br>That is, you decrease the size and power of the venturi flows?<p>This is of course also why the rear widnow gets less dirty, the dirt is not "sucked up" as high.<p>Any fluid dynamics engineers on this list? <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/smile.gif" BORDER="0"> </TD></TR></TABLE><p>I'm not a fluid dynamics engineer but I play one on the internet. You are right, though. Also consider that the V's rear is rather large, and the high pressure air bleeding off into the low pressure zone is rather turbulent, causing buffeting around the rear area. Feeding some high pressure air also helps to make the detachment of the air flowing around the body much more laminar and reduce instability. This is the reason that small lip spoilers such as the one on the R and M3 make a big difference. It's not the downforce, it's cleaning up the airflow.
 

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Re: Does V70R rear roof spoiler make a difference in handling? (needsdecaf)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>needsdecaf</b> »</i></TD></TR><TR><TD CLASS="quote"><p>I'm not a fluid dynamics engineer but I play one on the internet. You are right, though. Also consider that the V's rear is rather large, and the high pressure air bleeding off into the low pressure zone is rather turbulent, causing buffeting around the rear area. Feeding some high pressure air also helps to make the detachment of the air flowing around the body much more laminar and reduce instability. This is the reason that small lip spoilers such as the one on the R and M3 make a big difference. It's not the downforce, it's cleaning up the airflow. </TD></TR></TABLE><p>Yes, you are correct, oh wise internet engineer. Those of you who regularly explore the upper speed envelope of the V-R may consider vortex-generators on the underside of the spoiler, which would theoretically smooth the flow under the spoiler and generate more negative lift. Or something like that...
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Dashdog)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Dashdog</b> »</i></TD></TR><TR><TD CLASS="quote"><p>Yes, you are correct, oh wise internet engineer. Those of you who regularly explore the upper speed envelope of the V-R may consider vortex-generators on the underside of the spoiler, which would theoretically smooth the flow under the spoiler and generate more negative lift. Or something like that...</TD></TR></TABLE><p>All this AND a CLEAN WINDOW = Volvo Greatness. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/sly.gif" BORDER="0"> <IMG NAME="icon" SRC="http://********************/smile/emcocktl.gif" BORDER="0">
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Dashdog)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Dashdog</b> »</i></TD></TR><TR><TD CLASS="quote"><p>Yes, you are correct, oh wise internet engineer. Those of you who regularly explore the upper speed envelope of the V-R may consider vortex-generators on the underside of the spoiler, which would theoretically smooth the flow under the spoiler and generate more negative lift. Or something like that...</TD></TR></TABLE><p>Aha - something like this??? <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/eek.gif" BORDER="0"> <p><IMG SRC="http://www.craigfr.com/rice/wings.JPG" BORDER="0">
 

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Re: Does V70R rear roof spoiler make a difference in handling? (FastWgn)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>FastWgn</b> »</i></TD></TR><TR><TD CLASS="quote">Aha - something like this??? <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/eek.gif" BORDER="0"> <p><IMG SRC="http://www.craigfr.com/rice/wings.JPG" BORDER="0"></TD></TR></TABLE><p>And to think that there is some poor schmuck looking for the parts stolen off of his helicopter... If only they knew that Civics could fly! (sic) <IMG NAME="icon" SRC="http://www.vwvortex.com/zeroforum_graphics/screwy.gif" BORDER="0">
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Prospero)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Prospero</b> »</i></TD></TR><TR><TD CLASS="quote"><p>And to think that there is some poor schmuck looking for the parts stolen off of his helicopter... If only they knew that Civics could fly! (sic) <IMG NAME="icon" SRC="http://www.vwvortex.com/zeroforum_graphics/screwy.gif" BORDER="0"> </TD></TR></TABLE><p>Especially note how he went for the weight reducing approach and removed the side molding. That's heavy and serves no purpose.....<p> <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/biggrin.gif" BORDER="0"> <br>
 

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Re: Does V70R rear roof spoiler make a difference in handling? (FastWgn)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>FastWgn</b> »</i></TD></TR><TR><TD CLASS="quote"><p>Aha - something like this??? <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/eek.gif" BORDER="0"> <p><IMG SRC="http://www.craigfr.com/rice/wings.JPG" BORDER="0"></TD></TR></TABLE><p>That reminds me of something I saw the other day...<p><A HREF="http://www.villagehobbycentre.com/jokes.html" TARGET="_blank">http://www.villagehobbycentre.com/jokes.html</A>
 

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Re: Does V70R rear roof spoiler make a difference in handling? (Dashdog)

Dunno, it reminds me of this... <IMG SRC="http://upload.wikimedia.org/wikipedia/en/b/b9/Stormtrooper.jpg" BORDER="0"><p>On-topic, I agree the spoiler is pretty much all for drag and keeping the window clear. No downforce to speak of...<p>Tom.
 
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