Smooth wheel covers

Today I made wheel covers to block airflow through the factory 14" alloy wheels of the Mirage, in hopes of improving aerodynamics.

http://mirageforum.com/forum/attachm...1&d=1385344952


Now it's got that gangsta/hypermiler look to it :)

Yeah but how did you do it? - Well, I'm glad you asked. If you want to see a little how-to,then read on.

I had some plastic sheet signs. (not coroplast). About 1mm thick(or thin rather). Enough for four 14" circles.

A little brittle,it breaks when bent 90 degrees but decided to give it a shot.

The alloy wheel is curved so a flat sheet will not work. We need to get it convex.

I have a homemade english wheel (I just realized most everything I own is homemade..darn!),that is basically a large C-clamp where you pinch sheet material between a curved roller and a flat roller and as the sheet is moved back and forth,the material stretches so one can make compound curves if done correctly.

Starting out

http://mirageforum.com/forum/attachm...1&d=1385346267



Work it on the inside of the circle (not the edge)'till it buckles up.

http://mirageforum.com/forum/attachm...1&d=1385346607



Then the trick that worked for me was to turn it over and roll around near the edge but not touching the edge!

This seems to stress the material to pop the dome out where the material was previously stretched around the middle.

http://mirageforum.com/forum/attachm...1&d=1385346907

http://mirageforum.com/forum/attachm...1&d=1385347028



Checking humpyness and fit:

http://mirageforum.com/forum/attachm...1&d=1385347125



Then I removed a wheel so I can trace and mark for mounting holes around the spokes and after drilling I painted them flat black.

When that dried I mounted them with zip ties! What a pain in the neck that was with the wheels on!

Close up:

http://mirageforum.com/forum/attachm...1&d=1385347729

Test drive up to 78 MPH and they stayed on so I hope they survive for a while.

To check tire pressure I will just cut a couple of the zip ties and hopefully get to the valve stem.:)

It's a good idea just like the long distance bicycles and solar powered cars but certainly not made for sporty drivers as it will cover airflow that is used to cool down the brakes. Ur cover will make the brake overheat easily especially when used in warmer countries such as asia. It will result braking failure and may cause accident.

this is great
for hypermilers etc this would not be a problem because braking will be far less

i have seen this on other cars to and they have no problems with over heating brakes..

but they al drive normal and not like they have to get home because the house is on fire.

Nice work are going to test for fuel economy improvement with these?

Nice write up. Its been added to the fuel economy thread index. :)

Quote:

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Originally Posted by m4v3r1ck

It's a good idea just like the long distance bicycles and solar powered cars but certainly not made for sporty drivers as it will cover airflow that is used to cool down the brakes. Ur cover will make the brake overheat easily especially when used in warmer countries such as asia. It will result braking failure and may cause accident.

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Thank you for your concern! It is not for everyone. This appeals to fuel economy conscious people whom are far from the sporty brake stumping drivers.

On the other hand this will not thermally insulate the rotors as there is still airflow on the inside. But I agree, one should not enter the 24 hour lemans with the wheel covers :)

Quote:

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Originally Posted by jamiec

Nice work are going to test for fuel economy improvement with these?

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Thank you! I did it to improve fuel economy but I can not really see an instantly measurable difference due to all the variables like traffic, temperature,wind etc. I can only hope that it is working :)

Quote:

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Originally Posted by Daox

Nice write up. Its been added to the fuel economy thread index. :)

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Thanks Tim! I was looking for a DIY section like over at EM but couldn't find one so I posted it here.

hmm maybe I'll try that with MY home made english wheel:) awesome bro, crap you can probably easily make a full belly pan etc.

Wow - home made english wheel!

Going to make an access hole for the valve stem to check tire pressure?

Any other aero-modifications planned?

Quote:

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Originally Posted by kalifornia

hmm maybe I'll try that with MY home made english wheel:) awesome bro, crap you can probably easily make a full belly pan etc.

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There you go! Yeah I'm glad I'm not the only one with this homemade-mania:)

Quote:

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Originally Posted by MetroMPG

Wow - home made english wheel!

Going to make an access hole for the valve stem to check tire pressure?

Any other aero-modifications planned?

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Not planning on the access hole for now. I was hoping to cut not more than a couple of the zip ties and gently pull the cover away from the rim. We'll see if that works.

I checked tire pressures before mounting the covers and they were at around 46 PSI so I left it at that.

Other aero-mods,yes. Planning a small airdam, maybe a front belly pan, maybe a rear wheel skirt but only if it turns out nice and color matched.

And if I'm still not happy with the improvements I might just go ape crap on it and do full belly pan, aero mirrors,extended kamm back,lowering etc.

The homemade english wheel works pretty good for this kind of light duty stuff. bearings(rollers) came from a store called tractor supply (yeeeehaa) the tension adjusting on top is a telescopic steering intermediate shaft with a nut welded inside it and an all-thread rod with a knob welded at the end is how I run it up or down.

The rest is square tubing welded together with my ready for this?...homemade stick welder. Which is two car batteries in series and proper cables...the more I say the more I have to laugh. :)

Haha i really hope it will makes difference ;-)

Quote:

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Other aero-mods,yes. Planning a small airdam, maybe a front belly pan, maybe a rear wheel skirt but only if it turns out nice and color matched.

And if I'm still not happy with the improvements I might just go ape crap on it and do full belly pan, aero mirrors,extended kamm back,lowering etc.

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Looking forward to your work on this and the results:D

I don't have the skills or tools that 3dplane has, so I decided to purchase some smooth wheel covers made by Hella. They have an access panel for the valve, but I haven't tried getting my pump head in there yet. Its a pretty small hole.

The wheel covers fit snug up to the rim, unlike my stock hubcaps that kept a 1/8-3/16 inch gap between the cap and the rim.

I taped over the vent holes from the inside, with aluminum tape.

Attachment 829Attachment 830

I like those^
However I cannot seem to find them by Hella, everything I try keeps pulling up their lighting. Any help?

Those are cool !

Quote:

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Originally Posted by fifteenwindow

They have an access panel for the valve, but I haven't tried getting my pump head in there yet. Its a pretty small hole.

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You can also just get a valve extension/adapter (couple of bucks for a set). Easier to screw that on, and the tip is outside the small opening, then pump.

I like those too! Spill the beans, where did you get them? :)

I found them on eBay. I don't know of any other sets available.

A warning on these caps: they are not as sturdy as the stock caps. The wire hoop that goes around the inside is made of a smaller diameter wire.

Driving around today I lost a hubcap between Farm and Fleet (where I picked up some valve extensions (thanks, Metro)) and the library. I was Super Lucky to find it up on someone's lawn, as I retraced my route.

Fair warning.

DO they actually help?

Testing on ecomodder.com shows that they give anywhere from a 1-5% increase in fuel economy.

http://ecomodder.com/wiki/index.php/Smooth_wheel_covers

I don't have any proof or even real evidence that they do anything. I am going on what I have read on sites like Daox mentioned. Mitsubishi somewhere wrote that the mirage gets better gas mileage with the steel wheels & hubcaps than with the aluminum mag wheels because of a higher aerodynamic drag on the aluminum wheel.

I am trying to get the best gas mileage that I can, without doing expensive modifications. These hubcaps cost me $35.

If they work, it may take a year or so to get that money back. After that, it's like getting free money every time I drive.

my car was from the stock and came with alloy wheels (Mitsubishi incentive), unfortunately. Steel wheels would make the fixation of wheel caps easier.

Any ideas on how to fix wheel covers on the alloy mounts?
Otherwise I will smooth the wheels with duct tape.

Quote:

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Originally Posted by fifteenwindow

I don't have any proof or even real evidence that they do anything. I am going on what I have read on sites like Daox mentioned. Mitsubishi somewhere wrote that the mirage gets better gas mileage with the steel wheels & hubcaps than with the aluminum mag wheels because of a higher aerodynamic drag on the aluminum wheel.

I am trying to get the best gas mileage that I can, without doing expensive modifications. These hubcaps cost me $35.

If they work, it may take a year or so to get that money back. After that, it's like getting free money every time I drive.

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They should be just as good as the smooth hubcaps I got. Looking good!

Quote:

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Originally Posted by Donut

my car was from the stock and came with alloy wheels (Mitsubishi incentive), unfortunately. Steel wheels would make the fixation of wheel caps easier.

Any ideas on how to fix wheel covers on the alloy mounts?
Otherwise I will smooth the wheels with duct tape.

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I had to fix mine on the alloy wheels with LONG zip ties! They are still on and they held up to 90 MPH speed one time.

I say LONG zip ties because it was hard to loop the zip ties around the spokes, (I do have large hands though)

Sorry, I was wrong about what Mitsubishi wrote. It was what Metro wrote in this thread entitled How wheel & tire size and style affect Mirage fuel economy/mileage:

http://mirageforum.com/forum/showthr...conomy-mileage

Quote:

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•that flat plastic 14 inch wheel cover is probably more aerodynamic than the open spoke alloy wheel

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Thanks to the good folks on this forum for the sharing of ideas.

I've learned some things about hubcaps the last few days. One is that parts may be interchangeable between hubcaps by different makers. The stronger steel ring in my Mitsubishi hubcaps fit well in my Hella hubcaps.

The second thing is that 1/4 inch gap on the Mitsubishi hubcap (between the hubcap and outer rim of the wheel) may be there for good reason. It leaves room for wheel weights on the rim.

The Hella caps I bought snuggle right up to the wheel, or try to. Where there's a wheel weight, there's a gap, and the hubcap doesn't attach securely. The hubcap that fell off my car yesterday was on the one wheel that has 2 wheel weights attached, 90 degrees apart.

Today I made small cutouts in the hubcaps to accomodate the clamps of the wheel weights. The hubcaps now fit snug to the wheel all the way around.

Attachment 842

Now my hubcaps are wheel specific. I'll need to make new cutouts when I replace the tires, as the new weights will likely be in different places on the wheel. I hope all this work was worth it, but it was fun to do anyway.

Sorry, I'll stop talking about hubcaps now.

I was going to order a set, but I don't want to do it just to have one come off. I like that the ring can be swapped for the Mirage ones. I found some solid covers in stainless steel, but they were twice as much as these; however they were for racing, so maybe they'd stay on really well. Now I'm stuck and can't make a decision.......:confused:

http://www.ebay.com/itm/360342369177...84.m1423.l2649

These are the solid covers made from stainless I was able to find, just not excited for the price; also no valve cap access. This may be remedied by drilling a hole and longer valve stems. If these actually stay on in day to day driving, at $84 they may not be a bad option to consider for most people. I saw the pizza pan hubcap covers, cannot remember exactly where; possibly over on the ecomodder site. I showed them to my wife, she seemed less than enthused that I even considered it lmao.

Here's a thought:

Mitsu's plastic wheelcovers are pretty darn flat/smooth (currently one of the smoothest OEM ones I know of). Replacing those with perfectly smooth covers probably isn't going to make a significant MPG difference -- too small to easily measure. So if your goal is saving money, you'll have a veeeeeeery long payback time if you spend much money at all on replacements.

On the other hand, the cars with alloy wheels are going to see the bigger improvement, so could afford to spend a little more. Bang for your buck, in both cases DIY is the way to go of course.

Aesthetics are usually the issue with DIY.

posted this over in the wheels/tyres/suspension section, possible cheap junkyard alloys, have a set from my old car which i'm going to throw on for the next tank.

http://mirageforum.com/forum/showthr...-eco-quot-mags

may as well wear down the tread on the old wheels anyway and save the tyres on my stock alloys.

edit: disregard, my logic was flawed, hub centre of mirage is too large :(

Quote:

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Originally Posted by MetroMPG

Here's a thought:

Mitsu's plastic wheelcovers are pretty darn flat/smooth (currently one of the smoothest OEM ones I know of). Replacing those with perfectly smooth covers probably isn't going to make a significant MPG difference -- too small to easily measure. So if your goal is saving money, you'll have a veeeeeeery long payback time if you spend much money at all on replacements.

On the other hand, the cars with alloy wheels are going to see the bigger improvement, so could afford to spend a little more. Bang for your buck, in both cases DIY is the way to go of course.

Aesthetics are usually the issue with DIY.

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I used to think that alloy wheels were lighter as well but have found that steel rims are lighter....alloys became popular for looks,most people (including me) bought into the weight reduction story...

I saw a DIY somewhere on making smooth wheel covers out of hubcaps, old T-shirts, and epoxy resin. The T-shirts were stretched across the face of the hubcap, and secured behind it with a zip tie. Then resin was painted on across the face of the t-shirt, where it was stretched across the hubcap. Let the resin dry, cut the shirt off where it goes over the back of the hubcap. Smooth wheel covers are the result.

I'm finding myself debating as to whether or not to keep my coroplast wheel covers on. It looks better with the VX rims open, and just going to work and back it doesn't affect the fuel economy much at all, but it's definitely noticeable on the freeway. Taking them off and putting them back on frequently is a bit of a pain, especially since it's 32 zip ties to attach them.

I'd like to see what a set of Aluminum Moons would look like on the Mirage... I may look for a set at the swap meets this summer. They are kinda pricey new. 38 bucks a piece for new 14 inchers...