I drive a 1994 Geo Metro GE with a 3 cylinder engine. According to the official fuel economy ratings for this car, it should get 38mpg city and 44mpg highway.

I got this car as a gift from a friend. When I went to pick the car up, we had to remove the weeds that had grown up around it and relocate the family of field mice living in the engine compartment. I towed it home and replaced the alternator, a belt, the instrument cluster, and a frozen caliper to get it running.

The gas mileage was pretty good. I got about 35mpg city. I know this car can get more, so I started researching how to improve it. One of the things I found was smooth wheel covers. They are supposed to add around 4% to the fuel economy at highway speeds. This is only a small increase, but with other small changes, it should add up quickly.

I made my own smooth(ish) wheel covers. They look pretty cool and cost me less than $30 to make.

Step 1: Needed Materials

Wheel Covers
I got my wheel covers from ebay for $15. They are just inexpensive, plastic wheel covers.

Fiberglass Resin
This is available at hardware stores, auto parts stores, boating supply stores, and online. I bought mine for $12.

T-shirts x 4
Any t-shirt will do as long as there is a large enough section without any screen-printing. The shirt needs to cover the entire front of the wheel cover with a little extra for securing it in place. I just bought 4 large t-shirts Goodwill for $0.99 each. The third picture shows what happens to the shirt after this project, so don't use one you like wearing; it will be quite drafty.

Mixing Bucket
Any bucket will work, but you probably won't want to use the bucket for anything other than resin mixing after this. Lowe's has inexpensive plastic mixing buckets in various sizes. I bought the single quart size.

Acetone
Acetone is pretty easy to find. You can get it at hardware stores near the paint thinner. This is necessary for clean-up. Between the acetone, bucket, and paintbrush, I spent $12 at Lowe's.

Mixing Stick
Just a stick to mix the resin with. I used a scrap of wood that I had laying around. A paint mixing stick will work. Just make sure to wipe any loose debris from whatever stick you use to keep the resin fairly smooth.

Paintbrush
Any paintbrush will work. If you intend to use the paintbrush more than once, though, get a natural one. The acetone could damage the plastic kind and cause you some frustration.

Razor Knife
Just a basic box knife.

Diagonal Wire Cutters
The wire cutters are useful for the finishing touches, but a tough pair of scissors could also do this job.

Scissors
For cutting the t-shirt.

Cable Ties
The locking, single use kind.

Spray Paint (optional)
For coloring the wheel covers.

Gloves
Keep your hands chemical-free!

Sand Paper
For scuffing the wheel covers. I used a sanding sponge.

5-gallon Bucket (optional)
For a sturdier work surface.

Step 2: Preparation

Use some sand paper to rough up the surface of the wheel cover a bit to help make sure the resin will stick. Clean off the dust with a damp rag.

If your wheel cover has a tension ring, remove it now.

Put the wheel cover in the t-shirt facing the side with no printing on it.

Make sure to position it so that all the holes can be gathered easily into the center at the back of the wheel cover.

Put the tension ring, if you have one, back on.

Carefully pull the shirt as tight as you can without tearing the shirt or breaking the cover.

Gather all the loose t-shirt in the back and secure with a cable tie. You may need to use more than one depending on length.

Put the wheel cover on a sturdy surface with the front facing up. If you have a 5-gallon bucket, you can put the wheel cover on that with the t-shirt hanging down into the bucket.

Step 3: Resin Application

Do this outside. The can says to mix the resin in a well-ventilated area, but outside is best. This stuff burns the nose and smells awful. The fumes are pretty toxic, too.

I highly recommend wearing gloves. You can clean the resin off of your hands with acetone, but it will dry your hands and may irritate your skin.

Mix enough resin for one wheel cover since the resin cures very quickly and you will only have a few minutes to work with it. If you use a 1-quart can of resin, then use about a quarter of that. Follow the instructions on the can for mixing. Mine was a quarter of the liquid from the can mixed with a quarter of the liquid from the tube, but different brands may vary, so read yours.

Starting at the center, paint the resin onto the t-shirt working outward to the edges until it is well saturated and you can see the wheel cover through the shirt. It will not be completely transparent, but you should be able to see some definition.

In the time it takes to do this, the resin will get gummy in the paintbrush. When you have finished one wheel, clean the brush with acetone and either clean your mixing bucket or let the resin in it cure completely. I found it simpler to just clean it when I cleaned my paintbrush between each wheel cover.

Do all four wheel covers the same way.

Allow the resin to cure completely. My resin required 2 hours, but, again, brand requirements may vary. I actually left mine to cure overnight because I ran out of light.

Step 4: Removing Extra T-shirt

Remove the tension ring, if you have one, and trim the t-shirt along the edge of the wheel cover with a pair of scissors.

Clear off any small drips down the sides with a razor knife, and use wire cutters for larger drips.

Replace the tension ring and your wheel covers are useable.

Step 5: Painting

While the muddy brown of resin does not affect the useability of the wheel covers, it is ugly. To rectify this, just paint them. Pretty much any spray paint should work, but I used a black automotive primer I had left over from another project.

After shaking the can thoroughly, hold it about eight inches from the wheel cover and spray using a sweeping motion from side to side. This is a great project for practicing your painting technique. Allow the covers to dry, then install them on your car.

Step 6: 2 Months Later

In the time since I made these (about 2 months ago), I have only had to do two repairs to them.

The first repair was from when I accidentally popped a small section of one edge off while doing my brakes. I used a pry-bar to pull the wheel cover off the wheel, but I grabbed the wrong edge and it popped loose a bit. I fixed it with some super glue, and it has stayed just fine.

The second repair was purely cosmetic. I misjudged a turn and ran my wheel into a curb. Some of the paint scraped off and I had to give it a quick spray.

I like the look from the smooth(ish) wheel covers, and my gas mileage is currently 38mpg city. The tiny gas economy improvement isn't much, but with the other modifications I intend to make to my car, they will be worth the little bit of time and money I put into them.