Hubcaps?

[DracoFelis]

Do smooth hubcaps (for example, a "Baby Moon") help with FE? Has anyone tried it? If so, how much did it help?

This seems to me like it might be one of the easiest aerodynamic mods to make (since you just buy the hubcaps, and put them on). And it is pretty cheap to buy a set of hubcaps. But does this help? My thinking says it could go either way:

1) It might hurt FE, because the wheel covers will weigh something, and this will (slightly) raise the weight the wheel has to turn. OTOH this added weight isn't that high (especially compared to the weight of the tire and wheel itself).

2) OTOH it might help FE, because smooth hubcaps should make the wheels more aerodynamic, by covering over the places the air can get trapped in.

Either way, this mod should be reasonably cheap and easy to do (just buy a set of hubcaps, and put them on). And unlike some aerodynamic mods, this one isn't likely to draw a lot of attention to itself (as many people snap hubcaps on their wheels). And it should even cover up the rust on the wheels themselves.

But has anyone tried this (and if so, how well did it work)?

[ketel0ne]

See this thread.

http://www.gassavers.org/showthread.php?t=1449

On a side note I am kicking around putting them on my Yaris.

[ZugyNA]

Somebody just did full moons...even had pics.

http://www.jcwhitney.com/autoparts/P...p?Ntt=hub+caps

http://www.jcwhitney.com/autoparts/P...p?Ntt=hub+caps

[SVOboy]

As a general rule of thumb, I think aerodynamics > weight for FE.

One of the newer members just did this actually, but I haven't seen any results yet: http://www.gassavers.org/showthread.php?t=1449

I say go for it. Basjoos has done it as well. Other people I'm forgetting at the moment, sorry guys/gals!

Edit: Damn, I got pwned.

[MetroMPG]

My wheel covers are also smooth, but they don't necessarily look it in the photos due to my awesome fabricating skills.

Some actual figures to chew on:

Indeed by completely sealing all four rims, Cd can be reduced by 0.08 to 0.012 (ref. 6). The maximum drag difference between a good and a poor set of rims is probably even larger.

Source: Contribution of different devices to the total drag
http://www.tfd.chalmers.se/~lelo/rvad/reports/rva2002_gr11_contribution-to-drag.pdf

There's a section in that report devoted specifically to wheels, rims and wheel housings.

Edit: my wheel covers were pretty well designed to begin with, so my gain is likely on the small end of the scale (and further reduced by the rear wheel skirts). Small enough that I haven't tested it, and probably won't bother.

[Matt Timion]

Once I get my 14 inch tires (Ahem Bunger) and LRR Insight tires, I'll get some smooth hubcaps too... why not?

[lindermant]

I'm working on my first full tank with the moon caps installed... I'm only about 200 miles into the tank, and I'll be out of town for the next two weeks after I get off work Friday morning so I won't have data to share for awhile (unless I decide to fillup on my way home - but I hate short-tanking).

No promises, but my SG tank MPG reading is showing a tad higher than my last tank of 50.16MPG, which was a personal best.

No issues with brake temps, but the darned things are noisy at slow speeds!

[Ryland]

I rather question my vx rims at times because of my expearince with bicycle wheel airodinamics, the spokes of a bicycle wheel work alot like an egg beater, each spoke stiring up the air, thus the justifide demand for blade like bicycle spokes for racing, and me left wondering how good the 8 spoke vx rims really are, so it makes sence that the hybrid civic has wide flat spokes, and the insight has near disk rims with smal vents around the outer edges, so the worst rims you can get, airodinamic wise would be the ever so popular thin spoke large diamiter alloy rims (the spokes look thin, but are really wide flat blades, like a whole bunch of little fan blades...
We just got some of the spun alluminum Moon hub caps for the metro, but we haven't owned it long enough to have a solid feel of the mileage, nor do we have a scangauge yet and I haven't taken the time to find out what they weigh, but I'm sure I'll do it at some point.
either way, unless you get some heavy stainless steel caps or something crazy like that, smooth caps should help.

[JanGeo]

I noticed the water spray out of the rear wheel well of other cars on Tuesday highway trip and it seems that a lot of spray comes off the top of the tire blowing forward and then out of the top of the wheel well. That has got to be wasting power. I think a layer of clear shrink wrap over my hubcaps will have some effect - need to find a wide piece - I think I have some from a laser toner cartridge shipment that should be wide enough - pop off the caps wrap and pop them back on.

[cfg83]

I have had the snap-in baby moons. They are gorgeous but they fly off in a good bump (always my front passenger rim, maybe it's a front wheel drive physics thing particular to my previous Saturn coupe). The "real" baby moons that you see on hot rods are screwed onto the wheel rim.

How about the "floating hubcaps" that are on Taxis? I have a bunch of URLs but none of them look exactly like the ones I have seen in Los Angeles. Also, it doesn't look they are offered retail. You need to buy them in mass. Finally, they are not "flush", there is a gap between the tire rim and the floating hubcap, or the circumference is slotted, so I don't know if that negates the benefits of the flat hubcap (the ones in LA do look cool, though).

http://www.adcaps.com.au/pages/about.html
http://www.visiononwheels.com/Hubcap...dvertising.htm
http://www.hubads.com/products/abs.htm
http://www.adcapscanada.com/html/gallery.php
http://www.media-wheels.fr/ (in French)
http://www.tradekey.com/selloffer_li...dvertising.htm
http://www.alibaba.com/member/autopure/product.html

[zpiloto]

Originally Posted by cfg83

I have had the snap-in baby moons. They are gorgeous but they fly off in a good bump (always my front passenger rim, maybe it's a front wheel drive physics thing particular to my previous Saturn coupe). The "real" baby moons that you see on hot rods are screwed onto the wheel rim.

How about the "floating hubcaps" that are on Taxis? I have a bunch of URLs but none of them look exactly like the ones I have seen in Los Angeles. Also, it doesn't look they are offered retail. You need to buy them in mass. Finally, they are not "flush", there is a gap between the tire rim and the floating hubcap, or the circumference is slotted, so I don't know if that negates the benefits of the flat hubcap (the ones in LA do look cool, though).

http://www.adcaps.com.au/pages/about.html
http://www.visiononwheels.com/Hubcap...dvertising.htm
http://www.hubads.com/products/abs.htm
http://www.adcapscanada.com/html/gallery.php
http://www.media-wheels.fr/ (in French)
http://www.tradekey.com/selloffer_li...dvertising.htm
http://www.alibaba.com/member/autopure/product.html

You could put the GS logo on there.

[kickflipjr]

Floating hubcaps the "anti-spinner"

What WILL they think of next?

[WisJim]

I have a set of "Moon" discs (full wheel spun aluminum, snap on type) on our 2000 Metro, and it looks really cool!! The only disadvantage that I see is that you have to remove the hubcaps to check tire pressure.

[MetroMPG]

Or you could drill a 1/2 in hole and use a valve extension. That's what I did after I streamlined my stock wheel covers.

[ketel0ne]

Originally Posted by cfg83

I have had the snap-in baby moons. They are gorgeous but they fly off in a good bump (always my front passenger rim, maybe it's a front wheel drive physics thing particular to my previous Saturn coupe). The "real" baby moons that you see on hot rods are screwed onto the wheel rim.

How about the "floating hubcaps" that are on Taxis? I have a bunch of URLs but none of them look exactly like the ones I have seen in Los Angeles. Also, it doesn't look they are offered retail. You need to buy them in mass. Finally, they are not "flush", there is a gap between the tire rim and the floating hubcap, or the circumference is slotted, so I don't know if that negates the benefits of the flat hubcap (the ones in LA do look cool, though).

http://www.adcaps.com.au/pages/about.html
http://www.visiononwheels.com/Hubcap...dvertising.htm
http://www.hubads.com/products/abs.htm
http://www.adcapscanada.com/html/gallery.php
http://www.media-wheels.fr/ (in French)
http://www.tradekey.com/selloffer_li...dvertising.htm
http://www.alibaba.com/member/autopure/product.html

$350 for a set of 4 before the artwork.

Feel free to take the following idea and trick out your ride.

Mount 4 10" LCD's wired to a dvd player to them, or led's in changing light and color patterns. The ideas are endless .

[ketel0ne]

http://cripedistributing.com/stainle...ces-p-391.html

14" $18.00/4

http://cripedistributing.com/stainle...ces-p-390.html

15" $30.00/4

[cfg83]

Originally Posted by ketel0ne

http://cripedistributing.com/stainle...ces-p-391.html

14" $18.00/4

http://cripedistributing.com/stainle...ces-p-390.html

15" $30.00/4

I still can't believe how good this price is. You're getting four rims for the price of one. I am so depressed. When I traded my coupe for my wagon, I should have had the dealer switch the wheels. My (scratched) alloys are not compatible with my (covered in dust) wheel covers.

CarloSW2

[ketel0ne]

They came today, put them on tonight, drove around the neighborhood. They squeek a bit and each one fits just a bit weirder than the one before. I may need to buy another set, something tells me 1 or 2 of these are gonna come off. But they are exactly the same as the $80 and $100 sets.

[lindermant]

pics K-1, pics!

any chance you can adjust the inner "fingers" to get a bit more hold on the caps? It's all fun-n-games until you realize you've only got three hubcaps instead of four

[ketel0ne]

Originally Posted by lindermant

pics K-1, pics!

any chance you can adjust the inner "fingers" to get a bit more hold on the caps? It's all fun-n-games until you realize you've only got three hubcaps instead of four

I stretched em out a bit, ill see if i can make the whole commute in the morning and then check them, it got dark shortly after I put them on.

[Wazabi Owner]

I got my 13" discs for my Metro tonight as well. Haven't driven it yet to see/hear the squeeks. I doubt I could hear it over the alternator belt anyway, it's making a racket. Looks cool though. I wish I would of paid $18-$30 for them. I am gonna be mad if I lose one.

[JanGeo]

Any chance they squeek because the grab the outer edge of the rim instead of in deeper?

[ketel0ne]

I think it may just be the metal teeth on the metal rim. I may run a ring of 2 sided grip tape around the rim where the teeth grip.

[cfg83]

Originally Posted by ketel0ne

I think it may just be the metal teeth on the metal rim. I may run a ring of 2 sided grip tape around the rim where the teeth grip.

That's what it is. I tried duct tape on the teeth, but nothing got rid of the noise on my coupe.

CarloSW2

[DracoFelis]

Originally Posted by ketel0ne

I think it may just be the metal teeth on the metal rim.

Hmmm...

I wonder if it would help to paint a little "Plasti Dip" (paint on rubber coating) on the grip teeth? I know that rubber is flexible (so shouldn't be a problem with the movement of the teeth), and also tends to grip (non-slip) a little better than metal. So maybe it would be useful to cut down on the noise?

Edit: Fix typo in product name.

[ketel0ne]

Well, made it all the way in. With the windows up never heard them, 3 of them you need the lug/pry bar to pop them off the left rear you can get off by hand, still working on that one. Pictures later today, have gotten some stares and comments in the garage. Lead to more of is that a hybrid.

[JanGeo]

I'm thinking that something is flexing and making the squeeking noise - says something about plastic hubcaps doesn't it. Plastic dip would be a good idea as well as cleaning the rims. Anyone notice any FE improvement with the caps and have photos of them on the car? Would like to try a 15" set on my not so aero 7 spoke mag caps on my xB that surely must be pumping air around like crazy.

[ketel0ne]

A picture is worth a thousand words.

[JanGeo]

Yaaaaa Maaaannnn! sweet!

[cfg83]

Wow, that's a cool Yaris. If you have $100 lying around doing nothing, you could get them powder coated like I did oh so many years ago on my SC2 (RIP) :



Prediction : Within 4 months you will see a few more cars with racing disks in your neighborhood.

CarloSW2