Aero hub caps
 

I am thinking about making aero hubcaps from pizza pans.

http://i835.photobucket.com/albums/z...s/GEDC0135.jpg

How should I attach them?

If I have to screw them into the steely how should I do that?

I want the mod to be removable, and I want it to keep the wheel balanced.

I got my pizza pans today after church:
http://i835.photobucket.com/albums/z...GEDC0135-5.jpg

I also got some bolts that will work with my tap (5/16 x 18).

I was thinking of using the ridge in the middle of the tire to mount to:
http://i835.photobucket.com/albums/z...GEDC0138-5.jpg

http://i835.photobucket.com/albums/z...GEDC0139-7.jpg

does this look like a good mount point?

How many bolts should I use? 3,4,5?

Where did you buy the pans?

I'd use 3 bolts.

Walmart, $3.97 each!

What is the best way to center them?

Weather Spotter -

I am working on a successor to my serving trays that use pizza-pan *covers*. They have a lip. I measured the outer diameter, measured the diameter of the lip, and cut successive squares out of construction paper :

http://ecomodder.com/forum/member-cf...er-mandala.jpg

Since I have a 100mm 4-lug configuration (same as Honda Civics), I was able to use a square. If this worked for you, then your 5-lug wheel would need to use a pentagon.

That said, I haven't tested the result of this centering method yet.

Another mount point might be the circular holes in the steelie. You have 16 holes, so that implies a "4-point" mount system. I would experiment with this "pancake-hardware" method :

- Long bolt
- Washer bigger than circular hole
- Wheel
- Another washer bigger than circular hole in wheel
- Nut to hold "sandwich" in place
- Pizza pan
- Outer nut to hold pizza pan on.

There are a lot of problems with this. The circular holes aren't flat in relation to the pizza pan cover, so "truing" the long bolt will be a PITA. Also, if you screw it on too much, I could easily see the pizza-pan deforming.

PS - Those pans might rust quickly, so maybe a Rustoleum treatment is in order.

CarloSW2

I looked at the 16 hole option, the angle is very bad to work with.
I do not think that I can use the 5 wheel lugs as they are inset several inches.

As for rusting, I plan a full coating is some primer and paint!
Which looks better silver or black for the paint color?

Yes. When I made covers for my electric car I used 4 1/4"X20 screws in the top of the ridge as shown below. I had to number the wheels and covers because the holes ended up in slightly different locations on each wheel.

How well does the wheel balance for you?

I think if I use a template I might be able to swap them out (if I take my time and work it out).

Did you cut holes for the valve stems?

Did you use lock tight or anything on the bolts to keep them from coming off?

I made my covers out of a flat piece of fiberglass shower enclosure. I cut holes for the valve stems. On my wheels it turned out that the top of the ridge was in plane with the inside of the lip of the wheel, so flat stock fit perfectly.

I didn't use any locktight to hold the screws in, I just tightened them up with a screwdriver. No issues with balancing. The screws are so close to the center of the wheel that a slight difference in location doesn't matter. Just make sure that all the screws are the same length.

1. Put a grease cap on your hub, or the bearings may be starved of lubrication. While you're at it, prolly a good idea to re-lube the bearings, which may already be dry-ish.

2. Consider shorter valve stems, so you don't need to drill a hole in each pizza pan. Motorcycle valve stems? (At least, the ones on my bikes are shorter than those on my cars, but unsure if the hole in the wheel is the same.)

3. I would not drill into the steel wheel for fear of causing a weak spot, corrosion pathway, or imbalance. Rather, how about researching use of the balancing weight clips as mounting points. 3 holes, screws flush mounted by countersinking the holes in the pizza pans, or making dimples. Stainless steel screws. That said, you may have corrosion due to electrolysis between different types of metal with alu pans and ss screws. Anybody here know about this?

4. Velcro? If the pans fit snugly just over or inside the lip of the steel wheel, maybe adhesive-backed Velcro all around the rim would work. No rattles!

5. With pizza pans mounted, can the wheels still be balanced on a high speed machine? If so, you're balancing the whole package, much better than just the wheel/tire without the pan. Stick-on weights on inner surface of wheel should work.

6. What size wheels are those? Exactly how wide are the pizza pans? Fit just inside of just over the wheel rim lip?

The wheels are 16" so are the Pizza pans. that said, there is a nice gap of about 1/2" all the way around the pizza pan (I could not find 17" at a good price (under $12 each)).

I have looked at the wheel clip idea before, I do not think it will work for me.

Why should I add a grease hub when there is none on the car to start with? The bearings are all internal to the drive assembly.

Why I wanted holes for the valve stems was to check the air without having to remove the covers (the stems fit under the pan just fine)

Sounds like grease caps not a problem. One less thing to worry about.

Sounds like pizza pans fit inside the outer lips of wheels, i.e., pizza pans have 16" diameter vs. ~17" lip diameter of wheels. Does the inner radiused ring of the wheel protrude far enough outboard that the pizza pan will be flush against it? If so, and if the Velcro idea works, maybe put the Velcro there, with corresponding Velcro on inner surface of pans. I'm only speculating here about Velcro. Ideally, the outer edge of the pizza pans would fit just a bit snuggly inside the lip of the wheel rim, such that when you hit a bump, the wheel rim carries the load of the pizza pan, and the Velcro holds it down snug from flying off at highway speed. This idea a red herring if Velcro is a non-starter. Worth a shot? Thoughts?

The balancing weight shown in your wheel picture can be replaced with a stick-on type, leaving the rim uniform all around.

Here is how they look held in place:

http://i835.photobucket.com/albums/z...GEDC0139-8.jpg

Current:
http://i835.photobucket.com/albums/z...GEDC0138-5.jpg

the lip of the pizza pan just comes to the flat spot on the outer edge of the rim. there is less than a 1/4" overlap, not enough to do anything with. I think that the idea of Velcro is nice, but what ever I do will have to be with the ridge in the middle.

How bad would 3 bolts on the ridge be for rim integrity?

I'd worry about messing with the wheel itself, for fear of compromising it's structural integrity now or after any corrosion of holes drilled. But, let's hear from others more experienced in such matters.

I've not yet done any of this, but have an eye out for aluminum pizza pans for my Ford Econoline van with factory aluminum wheels. I'm hoping to find some to fit snugly just inside the rim lip, or perhaps just over it, to be self-centering. Just inside the rim prolly best, so when it hits a bump, the vertical load on the pizza pan is directly absorbed and contained by the rim lip, rather than side-stressing the pizza pan mounts.

I had the holes in my rims for 5+ years and had no issues. You're only removing about 1/18th of the metal in that area (circumference-wise). Compare how much metal you will have left in the ridge versus the area that has the pre-punched holes in it. I think the ridge has more, therefore, IMO it's a non-issue.

I wouldn't even want to try it.
When even the metal spring-type wheel covers won't always stay on (I've lost 2 while driving) , velcro really won't stand much of a chance .

I lost one of my OEM hub caps, and two others from having the clips not stay on.

I would doubt that velcro would hold with the crazy bumps in Michigan's roads (they are rather crappppppy!)

That being said, the pans are only $3...so it really wouldn't hurt to try!

As for drilling, I really would doubt that the holes would really damage the integrity of the wheel, so go for it.

I just might need to get my drill and tap out. I think I will try 3 bolts @ 120 degrees apart. That should hold well, while not drilling much out.

It's not the money, it's the risk of having them fly off.

Velcro could maybe be used as a back-up.

Update:
I did some work today and got the two front wheels covered!

How to:

Examine your existing wheels.
http://i835.photobucket.com/albums/z...GEDC0138-5.jpg

Buy pizza pans to fit (mine were 16" but 17" would have been better), Walmart had these for $3 each:
http://i835.photobucket.com/albums/z...GEDC0135-5.jpg


Locate a good spot for drilling and taping bolt holes: (in my case it was the ridge in the middle of the rim)
http://i835.photobucket.com/albums/z...GEDC0154-2.jpg

Drill and tap 3 holes spaced 120 degrees apart (measure with protractor). I made the holes in the pizza pans first then used that as a template for the rims. I messed up the first set of holes (they were in 1/2" to far):
http://i835.photobucket.com/albums/z...GEDC0153-5.jpg

http://i835.photobucket.com/albums/z...GEDC0155-4.jpg

Attach using bolts to that mach you tap (mine was 5/16 x18 and 1" long (.5 would have worked)):

http://i835.photobucket.com/albums/z...GEDC0157-1.jpg

http://i835.photobucket.com/albums/z...GEDC0158-2.jpg

Other side of car (notice only one set of holes):
http://i835.photobucket.com/albums/z...s/GEDC0160.jpg

Paint insides to slow rusting, I also put a layer of clear coat on the outside.

Very nice!! :thumbup:

They seemed to turn out pretty nice. I will be curious to see how they hold up. I have made one aero hubcap for my metro so far. I just laid some fiberglass down on top of the OEM hubcap and epoxied it up. I added some red paint to it for fun. The cap is not super smooth as I did no sanding or re-coating, but I think it will do the trick and it was both cheap and fast to do. I will see if I can post a picture later.

Switch to truss-head screws for a minuscule decrease in drag. :)

I might do that to save on/off time (can use a drill then). Do they come in galvanized?

I think so. You might consider stainless if they're not too expensive.

Himm, I see a trip to the hardware store in the making......

I used to use button heads on my go-kart, but you need an Allen wrench to use them: 5/16-18 x 5/8 Button Socket Head Hex Drive Cap Screw (Bolt) Qty (1) [BSCS51658C] - $0.16 : NutsandBolts.com

Did you take them back off or something? when I got back from work I didn't notice them on your car....

they are being painted (you missed them, they were 12 feet from your car.

At your MPG you might just catch up to me..... HA HA HA

Anybody looked at using hub cap clips scrounged from plain old hubcaps, now attached to pizza pans?

Otto -

Here's one :

The new 2004 Toyota Prius - My own hubcap
http://www.vassfamily.net/ToyotaPriu...InProgress.jpg

CarloSW2

Update:
This morning I made covers for the back wheels:

http://i835.photobucket.com/albums/z...GEDC0136-7.jpg

with rear wheel skirts to:

http://i835.photobucket.com/albums/z...GEDC0137-7.jpg

I did some ABA testing today..... results show a 1.48 MPG gain!
A= 45.15
B=46.54
A2 = 44.98

I had not expected this much gain for a $15 mod!

I have all the data but need to make a nice file (and graphs) yet, I will post that up when I have it done!

Looks really nice!!

Got any more close up pics of the kammback?

yep in this thread:
http://ecomodder.com/forum/showthrea...rix-14150.html

Testing data update:

Raw data:
http://i835.photobucket.com/albums/z...coversdata.jpg

Graph:
http://i835.photobucket.com/albums/z...versdata_2.jpg

Here is a better thread, it is my how to on my Kammback:
http://ecomodder.com/forum/showthrea...k-14159-3.html

Wow, I am surprised it made that much of a difference. Nice job! Now I really want to finish my aero hub caps. BTW, I like your Kammback and skirts.