Is the RX-8 Spoiler Functional?
#1
Is the RX-8 Spoiler Functional?
I was just wondering if the RX-8 spoiler actually does anything for the Drag Coefficient or not.
Prompted by a discussion in this thread @ RX7Club: http://www.rx7club.com/showthread.php?t=650877
Cheers,
Cody
Prompted by a discussion in this thread @ RX7Club: http://www.rx7club.com/showthread.php?t=650877
Cheers,
Cody
#2
Blue By You
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I was just wondering if the RX-8 spoiler actually does anything for the Drag Coefficient or not.
Prompted by a discussion in this thread @ RX7Club: http://www.rx7club.com/showthread.php?t=650877
Cheers,
Cody
Prompted by a discussion in this thread @ RX7Club: http://www.rx7club.com/showthread.php?t=650877
Cheers,
Cody
#3
Minimally. You'd need something big and obnoxious like the Evo or STI wind to really make any difference. Even then, just putting a big wing on isn't going to do much without wind tunnel testing and people with a very good understanding of physics and vehicle dynamics helping with the design.
So that's a VERY minimal difference. But interesting nonetheless. My wing is actually... "functional". :-P
Cheers,
Cody
#6
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I figured it'd be minimal. Someone said that the stock wing I have on my RX-7 reduces the Cd to 0.29. All the numbers I've found for stock RX-7s say Cd is 0.30.
So that's a VERY minimal difference. But interesting nonetheless. My wing is actually... "functional". :-P
Cheers,
Cody
So that's a VERY minimal difference. But interesting nonetheless. My wing is actually... "functional". :-P
Cheers,
Cody
#7
Cheers,
Cody
#10
This is generally true for a wing, but the "duckbill" he has on his RX-7 is a spoiler. Spoilers can help maintain laminar flow and delay separation. They can also minimize turbulence behind the vehicle, reducing "boattail" drag. So yes, it's not uncommon to hear of spoilers that reduce the Cd (albeit by a small amount). This is why I find it annoying when people criticize spoilers on FWD cars.
Last edited by Socr8tes; 05-11-2007 at 04:35 PM.
#13
you are brilliant!
i wish companies who made spoilers actually did some aero testing it would help me decide on which to buy.
i wish companies who made spoilers actually did some aero testing it would help me decide on which to buy.
This is generally true for a wing, but the "duckbill" he has on his RX-7 is a spoiler. Spoilers can help maintain laminar flow and delay separation. They can also minimize turbulence behind the vehicle, reducing "boattail" drag. So yes, it's not uncommon to hear of spoilers that reduce the Cd (albeit by a small amount). This is why I find it annoying when people criticize spoilers on FWD cars.
#14
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Most of the "euro lip" spoilers that are actually functional and necessary are found on cars with abnormally large low pressure areas over the rear deck lid behind the rear windshield. The Audi TT is one of those cars that gets a little evil at high speeds without it. The vast majority though are for appearance purposes only.
#20
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I was under the impression that a true "spoiler" (not a wing) is supposed to be curved on the bottom, and flat on top. Much like an upside-down airplane wing. As an airplane wing passes through air, lift is created. As the spoiler passes through air, downforce is created since the curved side is on the bottom instead of the top. Look at the OEM spoiler - curved on the bottom, flat on top.
I would assume that this would only have any noticable effect at extremely high speeds, though. I may be wrong, but it always seemed to make sense to me.
I would assume that this would only have any noticable effect at extremely high speeds, though. I may be wrong, but it always seemed to make sense to me.
#21
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I was under the impression that a true "spoiler" (not a wing) is supposed to be curved on the bottom, and flat on top. Much like an upside-down airplane wing. As an airplane wing passes through air, lift is created. As the spoiler passes through air, downforce is created since the curved side is on the bottom instead of the top. Look at the OEM spoiler - curved on the bottom, flat on top.
I would assume that this would only have any noticable effect at extremely high speeds, though. I may be wrong, but it always seemed to make sense to me.
I would assume that this would only have any noticable effect at extremely high speeds, though. I may be wrong, but it always seemed to make sense to me.
As far as the difference between spoiler and wing, I don't think they are really distinct and are pretty interchangeable.
#22
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Are there decent diffusers for the RX-8 out in the market? For real, tested and confirmed aerodynamically? I want to branch out from AX next year (saving for so much else at the moment) into track days and I know that the real front lip spoilers can create a serious amount of useful front-end downforce and would love to be able to balance that at the rear without a giganto wing.
I could also see these reducing Cd as well...
I could also see these reducing Cd as well...
#23
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Aero testing is amazingly expensive (it is still really pricey even if you own the wind tunnel). Most companies are not going to worry about engineering a perfect wing because the gains are so little compared to spending time developing the aero on different parts of the car.
#24
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Aero testing is amazingly expensive (it is still really pricey even if you own the wind tunnel). Most companies are not going to worry about engineering a perfect wing because the gains are so little compared to spending time developing the aero on different parts of the car.