skirts

[MetroMPG]

plastic wheel skirts, attached with velcro.

why plastic: lightweight, non-rusting, easy to work with.

why velcro: i didn't want to drill any part of the sheet metal in the wheel well, because it's one of the most rust-prone areas on a car, and ontario is in the rust belt.

that said, drilling and using some other kind of fasteners would definitely be faster and probably easier. also, metal would be fine, or if you're good with fiberglass. the basic layout/planning steps will be similar.

step 1:

tape newspaper over wheel well. try to make it taut and wrinkle free. trace wheel arch outlin

step 2:

use the arch tracing to make up a cardboard prototype. when cutting the cardboard, don't cut right to the edge of the tracing. you need extra material to fashion the curves to get around the tires and leave space from the wheel. and depending on your attachment method, you may be forming a 90 degree lip as i did, to mate to the lip in the wheel arch.

step 3:

make the plastic version...

step 4:

making the plastic version, continued...

- to give the plastic some rigidity and to hold the proper shape to clear the tires/wheel covers, i taped, then drilled and attached 3 screws through a strip of flat aluminum trim on the back of the skirt. (the trim is what you find on the floor in a doorway at the transition between different flooring types.)

step 5:

that's it. i didn't have to paint my skirts because the black plastic is a fair match for the paint (a coulple of shades lighter). fyi, the skirts don't look quite as nice as the pics suggest, but i'm happy overall.
time to complete:

4 to 6 hours.

velcro notes:

i'm confident the velcro is going to hold the skirts in place in all normal situations. the only thing i wouldn't do is subject the gap between skirt & wheel well to the blast of a pressure washer.

[Compaq888]

wow, I love this DYI. It is so direct.

[philmcneal]

YES SOMETHING THAT IS BLACK AND DOESN"T REQUIRE ME TO OPEN THE HOOD OF MY ENGINE! Metrompg your the man and hopefully I can cruise better than 60 mpg on the highway with some less drag on the back wheels!

CAN'T WAIT.... when i'm not lazy anymore of course.

[kickflipjr]

Metro you should of done this in the fall. It will be hard to find a krazy karpet this time of year.

I also think finding a maroon colored one might be impossible. Red might not look to bad on my car.

[MetroMPG]

true. the krazy karpets aren't on the shelves any more.

but there must be other things you can buy that are similar... i'd go browse around the Home Depot or equivalent. see what you can find.

also, re: paint - can't you buy cans of colour matched spray paint? there's an auto paint supplier in town that will make up a full size can of spray paint if i give them the car's paint code. it's about $18, but it's a good match. i've used it before.

also on the list: removable front wheel skirts. for highway use only... relatively STRAIGHT highways. or is that just too krazy?

[Compaq888]

true. the krazy karpets aren't on the shelves any more.

but there must be other things you can buy that are similar... i'd go browse around the Home Depot or equivalent. see what you can find.

also, re: paint - can't you buy cans of colour matched spray paint? there's an auto paint supplier in town that will make up a full size can of spray paint if i give them the car's paint code. it's about $18, but it's a good match. i've used it before.

also on the list: removable front wheel skirts. for highway use only... relatively STRAIGHT highways. or is that just too krazy?

yeah, that is going a little too crazy. How is your progress on the grill block??

[kickflipjr]

That is Krazy, but I bet you would get good mpg. It would be worth a test. How would you turn (I guess you don't)?

[rh77]

Props on the rocker panel flare -- nice touch! 8) Have you had any problem with suspension travel (camber) and the flare location? I hauled a heavy load this past weekend and noticed on my car that the independent suspension moves the wheel up and out considerably when compressed - as I'm sure most independents do.

I wonder how easy it would be to get a small can of stock paint and spray it with the car's color/clearcoat? However they get the paint to stick to plastic -- like bumper covers -- I'm clueless. Paint experts out there?

RH77
(KCØWPM)

[SVOboy]

I would just sand and primer the plastic to get it to stick. There is also plastic paint, so mehbe plastic specialty primer. Anyway, you shouldn't be getting camber because of load, that's scrizzey.

[Compaq888]

my wheels go more inside and so do my mom's car when there is more weight in the back.

[SVOboy]

Eww, that's so weird. I guess I don't have independent rear lcas though, :(

[Compaq888]

also on high speed cornering my rear wheels develop more toe in to stabilize the rear end. Never in the lifetime of owning the vehicle has the back ever slipped, even with ****ty tire. I did have some understeer when I made a high speed u-turn. On my cousin civic I turned really fast and the back slid out HAHAHAHA

[rh77]

also on high speed cornering my rear wheels develop more toe in to stabilize the rear end. Never in the lifetime of owning the vehicle has the back ever slipped, even with ****ty tire. I did have some understeer when I made a high speed u-turn. On my cousin civic I turned really fast and the back slid out HAHAHAHA

My old Civic was setup for autocross and did the same thing -- it was fun.

But yes, I had probably about 400-lbs. of bricks in the back of the Integra, and it had a nice, lowered look when parked (only in the back of-course). We never hit the bump-stops during the ride so, it was all good (who needs an SUV when you have a hatchback???)

Imagine a wheel pivoting on the suspension attachment point -- when it goes up, the 12-o'clock position tilts in while the 6-o'clock tilts out. You can really see it on the front of old worn-out Ford Tempos. The suspension sags in the back while the front wheels tilt outward due to the extension of the suspension. Watching them go over a bump shows the whole indpendent suspension process in excess (except the rear -- not indep.) -- the front wheels will tilt in and out over an undulation while the suspension goes down and up, respectively. Old, poorly maintained 300Z's have this problem in the rear as they sag over time as well.

RH77
(KCØWPM)

[MetroMPG]

How is your progress on the grill block??

haven't started. well, not true. i put some fresh tape on to keep the cardboard from falling off completely. i may go have a look at the grille block issue this evening.

Have you had any problem with suspension travel (camber) and the flare location?

no - but i haven't really checked it. there's about a 1.5 inch gap between the skirt and the wheel, so i'm thinking it'll be okay. plus the flare is out, not in, so there's actually slightly more space at the very bottom of the skirt. though it's hard to tell from that pic.

[philmcneal]

wow didn't know you can cover up the front wheels too and expect the reduce drag to have an affect there. By the way does water evenually unsticky the velco?

the only disadvantage i see with wheel skirts (besides the look) is that the fact if your trying to check pressure and the air nozzle is hidden, then that will be indeed a pain.

[Compaq888]

push the car forward or back to get to the nozzle. When I don't want to start my car I just move it forward or back.

[MetroMPG]

wow didn't know you can cover up the front wheels too and expect the reduce drag to have an affect there.

phil, check the pics in this thread:
http://www.gassavers.org/forum_topic/aerodynamics_performance_and_economy.html

By the way does water evenually unsticky the velco?

no - it's a mechanical connection between the two halves, and the adhesive holding the velcro to the car & skirt is waterproof.

as i mentioned though, i'd be careful with a pressure washer. directed high pressure water might peel the glue.

the only disadvantage i see with wheel skirts (besides the look) is that the fact if your trying to check pressure and the air nozzle is hidden, then that will be indeed a pain.

you know, i have slowly come to like the look. since the plastic skirts turned out nicely, i *really* like the look. though wheel skirts are probably the pocket protector equivalent in automotive fashion.

compaq's right - just roll the car to get to the valve. (or clean the wheel, whatever). it's just one more thing that's slightly more work to get slightly better mpg.

[rh77]

I noticed something else in your skirt pic. Have you altered the spaces in the wheels themselves? It looks like black inserts in the gaps with a hole for the valve stem. Is that stock, and if not, has it helped?

It would be a next to impossible for my 30-something-spoke wheels (and I'm sure covers to go over the entire wheel aren't made -- plus the concern that it would have an adverse effect on brake cooling).

[Matt Timion]

It would be a next to impossible for my 30-something-spoke wheels (and I'm sure covers to go over the entire wheel aren't made -- plus the concern that it would have an adverse effect on brake cooling).

From what I've read brake cooling is only an issue if you're braking a LOT... and by "a lot" i mean going down mountains on a regular basis. People here in Utah use their brakes going down mountains and don't konw why their cars catch on fire.

I think for the most part brake cooling isn't even to be factored in.

[Compaq888]

you can buy dish hubcaps that are completly covering your rim. They are exactly the same ones on that aerodynamic truck.

[MetroMPG]

today: sitting at a stop light, a guy in a purolator van pulled up in the next lane and yelled over "what's that cover over your rear wheel for?"

[thisisntjared]

thats cool that the guy appreciates it. who cares if someone doesnt like it. they can talk to the gas station attendant about it every week.

[kickflipjr]

Metrompg you will have get better comments then when you were driving around with cardboard.

[MetroMPG]

it made me wonder

[rh77]

I forgot Purolator was still in biz up there -- ours got absorbed by someone, UPS maybe. But you may be onto something with the employee reward thing.

I recall seeing these on the highways here (not many though).

http://pic16.picturetrail.com/VOL698/4382742/9261619/145994169.jpg

They claim to give a 4% increase in economy using the "SAE J1321" testing method (taken from http://www.freightwing.com)
Any fuel savings on large, long-distance carriers could help big-time. I haven't seen much in the wheel-covering department.

[MetroMPG]

Metrompg you will have get better comments then when you were driving around with cardboard.

it was still cold out when the cardboard was on and nobody was driving around with their windows open :)

cool pic, rick.

[rh77]

cool pic, rick.

Thanks man! :-) I don't think they cover the trailer's wheels because the wheel-set has to slide fore and aft to balance the load. On fixed-axle vehicles, there has to be a significant benefit in a wheel cover of some sort. Anyways, the picture probably shows the axle group in the front-most position.

[SVOboy]

Fix your pictures or you'll be beaten with a stick.

[krousdb]

Yes, I plan on doing some and pics are good. What would you charge for a set or red ones?

[MetroMPG]

I was going to wait until Matt gets back to fix the pics (remember we discussed a global fix for broken theimagehosting links). But if anyone's in a panic, I'll go ahead and do it.

[MetroMPG]

My beloved wheel skirts have been off the car for most of the summer.

[MetroMPG]

I see your FE is greater this summer (no skirts) than last summer (with skirts)!

That's true. It's because of driving technique (e.g. consciously aiming for a 100+ mpg fill-up using P&G exclusively) and lower average speeds.