Micro-mini Wheel Skirts

[Tourigjm]

i'd be willing to bet that the partial skirts would help.

the air above the tire is turbulent because of that sharp edge, as well as the rotating tire. eliminating the sharp edge would remove a large source of turbulence and i think that there would be little to no airflow above the tire in the wheel well. there's definitely some drag reduction.

best way to find out though is to actually test.

[crexcrex]

I admittedly expressed a point of view regarding partial skirts to the effect that partial skirts would only serve to trap turbulence thus eliminating any mpg gain.

Let me try and explain the idea of the full skirt as applied to my crx. The skirt is a full skirt made from3/16 abs backed with coroplast and affixed to the wheel housing with six nylon license plate screws imbedded into the back as to add to the cosmetic appearance.

I used a seal consisting of breath able 1/4 inch hose which i beleive is called soaker hose and the reason bieng was to allow the skirts to exhast excessive turbulence via the soaker hose. In addition the wheel housing underneath the vehicle comes to a abrupt curve which in effect served to trap the turbulence further. To resolve the problem i driled eight one inch holes into the lower wheel housing at the abrupt ending of the curve, this i did to both sides of the vehicle.

After having drilled the holes i bent the base of the abrupt ending of the wheel housing into a gradual curve to allow any further turbulence to escape.

A quick test drive proved out my theory that the full skirts were indeed effective.

The full skirts sit flush against the center pin for the racing disks and during the test run which was for a period of three months the skirts did not deviate from the position they were placed.
Were the full skirts ineffective the skirts would have flared away from the pin holding the racing disks.

There is a lot more to placing full skirts on a vehicle without thinking of the consequences of ones actions.
The air traveled over the skirts as i had expected and the work done underneath the wheel housings was well thought out.
let me say that i have worked on rear skirts for over two years verses a scan gauge test with out the work that i have done.

The full skirts in my opinion do work and it will take more that a tufft test, scan gauge test to debunk the effectiveness of rear fender skirts.

Had all of the work i had done been applied to the vehicle i am certain that your results would have been quite different.

I have sold my crx and with a little imaginatin i was turning 64.5 mpg consistantly............
I am now in the process of modifying a honda del sol...........

It is not my intent to make anyone believers of the full skirt or anything else, all i have done is share my work with others on ecomodders........whatever one decides to do will not be based on my experiences but based on the results pro's and con's that you have determined

The next set of skirts will be simplicity at it's best, all of the tufft testing and scan gauge readings will still indicate that rear skirts are ineffective contrary to a 4-5 mpg gain, don't ask me to prove it as results will differ, body work is my line of work and i do know what i am doing, 15 years perviously in the trade.............can you say the same? and a sculptor which means i know what lines it takes to effect smooth aerodynamic lines

As said before expressing an opinion as i beleive nothing is written in stone

crexcrex

[crexcrex]

Please note that the rear skirts were designed so that the rear bumper when bumped into would flex and not pop off, i wonder if anyone has given that any consideration. Plus the skirts have to be secure in order to ensure that no other person, cars etc would be injured by a improperly secured rear fender skirts.
Anyone can make a fender skirt they however must incorporate safety as well.
thankz

[COcyclist]

Your Micro-Mini skirts now look like some I saw on the front wheels in a photo of Aerohead's aero Honda CRX (he had full skirts on the rear). Even if you don't have a Scanguage have you been keeping a gas log? Over the long haul the gas log will tell the truth. I hope you can get us some data. I have been considering doing something similar myself.

[Xringer]

Originally Posted by Tourigjm

i'd be willing to bet that the partial skirts would help.

the air above the tire is turbulent because of that sharp edge, as well as the rotating tire. eliminating the sharp edge would remove a large source of turbulence and i think that there would be little to no airflow above the tire in the wheel well. there's definitely some drag reduction.

best way to find out though is to actually test.

I hope you're right and they do help some.

I plan to make a 200 mile road trip soon. If there is a noticeable change
in MPG, I just might see it on the way out (early before traffic hits),
but on the way back, I'll likely be forced to speed, along with all the nuts..
Still, I might be able to see if there is any change at higher speeds..

[Xringer]

Originally Posted by COcyclist

Your Micro-Mini skirts now look like some I saw on the front wheels in a photo of Aerohead's aero Honda CRX (he had full skirts on the rear). Even if you don't have a Scanguage have you been keeping a gas log? Over the long haul the gas log will tell the truth. I hope you can get us some data. I have been considering doing something similar myself.

If I get time this week, I want to add some Gorilla Zig-Zag tape to some of the frontal roll-off areas,
before I make my 200 mile round trip.
It's 95% highway and maybe I'll see some change in MPG on the Scangauge2. (I hope).

I'm an old absentminded dude and I forgot to write down the Tank MPG and Odometer readings at my last fill up. I just tweaked the gallons correction % -0.1 then hit the save and odometer trip-meter reset.. Next time, I'll leave my wife at home when I get gas..

Since I only buy 8 or 9 gallons a month, I'm lucky that I've got my scangauge working as well as it does.

Since I'm now driving 1000-2000 miles a year, this is a hobby thing for me, and I really don't try too hard to save gas when running around town. (My wife freaks when I turn off the ICE at a light).

My main interest is finding out if my Modded CRV can hit 35 MPG..
If I can do that, my work here is done.....

[tasdrouille]

My main interest is finding out if my Modded CRV can hit 35 MPG..
If I can do that, my work here is done.....

And then there'll by 40 MPG...daring you.

The skirts helps, that's been proven countless times. Everything you do to cover the wheels will help, be it a full skirt, mini or just reducing the fender/tire gap. The problem is that you might not see an improvement in your next tank because of many variables impacting your MPG which you can't control on a tank to tank basis. Just don't go and remove them after your next fillup because they did not live up to your expectations, that would be stupid.

[Xringer]

Originally Posted by tasdrouille

And then there'll by 40 MPG...daring you.

The skirts helps, that's been proven countless times. Everything you do to cover the wheels will help, be it a full skirt, mini or just reducing the fender/tire gap. The problem is that you might not see an improvement in your next tank because of many variables impacting your MPG which you can't control on a tank to tank basis. Just don't go and remove them after your next fillup because they did not live up to your expectations, that would be stupid.

I'm not going to take anything off, until I'm real sure it's harming the cd.
If I can get this monster to do 35 on highway, I'll see about replacing
some tape with plastic or sheet metal. I don't think I'll ever worry about 40
MPG unless I add an EV motor (for a mild-hybrid effect).

I just topped off today. I knew it was going to be bad before I went in,
since we wasted a ton of gas sitting in 4 MPH Boston traffic for at least
an hour, a couple of weeks ago.

Just about all the drivers around here a really bad rubberneckers.
They sit in stop-and-go traffic for hours complaining about it..
But when they get up to the jam's point-of-origin, they hit the brakes!
They have to stop and look all around to find out the reason
they were in the jam for so long!!

Most of the time, the tire changer is gone, but they stop anyways..
Sometimes, it's a new billboard, wastes millions of gallons of fuel!!
People see it and they hit the brakes!

I'm not sure what's going on here. But is sure seems like this state has
the dumbest drivers in the known universe.
And now the cell phone texting thing has made it worse!!

[pugmanic]

Originally Posted by lunarhighway

a few 80's and early 90's cars wich had quite good to exeptionally good Cd's used these cut off rear arches... unfortunately big wheel arches again became a fashionable in the late 90's and this smart feature disapeared.
here's a few examples of car wich more or less cut off rear arches... most have pretty great aero for their age


1986 opel omega 0.28 Cd (one of my favourites)

1984 opel kadett (later rebadged daewoo nexia and pontiac lemans) 0.32 Cd

The wheels arches on the Vauxhalls / Opels also had the propensity to attract the dreaded Tin worm. I suppose this is a form of weight reduction so not all bad

The Citroens were galvanised so didn't suffer in the same way.