Partial rear wheel skirts/deflectors?

[ECONORAM]

BZP, I only did partial skirts due to the amount of corroplast I had available. I mounted a 90* steel bracket at the front and back of the wheel well, on the truck where 2 of the screws already hold a wheel well tub in place (MOPAR part). I hate dirt all over...
Anyhow, with those brackets in place, I cut a piece of 2" wide window blind to about 36.5 inches long (give or take), and drilled 1/4 or 5/16" holes at either end to match the holes in the brackets. --I remembered your work with the pvc pipe and the steel bar, so I figured corroplast wouldn't be stiff enough on its own. Punched matching holes in the corroplast and used a 1/4" plastic push-thru fastener on the front, and a 1/4" bolt on the back (had too much gap for the plastic fastener). I also cut 2" x 2" tabs every 5 or 6 inches around the arch, and plan to stick them to the truck with self-adhesive velcro strips. I only had enough for 2 tabs; had to order more from Ebay.
Weather hasn't allowed any ABA testing yet...

[edit] and when my wife finally saw them two weeks later, she was MAD as a hornet! She doesn't like any mods that detract from appearance...

[edit 2] the bolt is at the front, the plastic push-thru at the back. I forgot.

[BamZipPow]

During heavy crosswinds, the truck has been influenced by the wind currents. I'm gonna run a tankful or two without the side skirts on and see how the truck will respond as well as the MPGs. Looks kinda strange without them on there...but it's all fer science!

Maybe I'll come up with another side skirt design that will allow crosswinds that exceed a certain amount of pressure on the side skirts to pass through instead...or even cut down the ones I have.

Sans side skirts...but the rear wheel skirts stay.

[ECONORAM]

I find it odd that you've noticed some cross wind issue. My truck is more stable with the addition of the belly panels, side skirts and wheel fairings. Have not tested the rear wheel skirts yet. Had to remove everything last week to get some new tires--Firestone Destination LE2s! Maybe I'll post a review after I drive on them a little more.

[BamZipPow]

I noticed the crosswinds affected my truck more so after I put the full rear wheel skirts on...along with the rear strakes.

Since running without the side skirts, crosswinds have had a lesser effect on the truck. I'm gonna have to do something about buttoning up the gap though.

[Viturro]

Good job with that truck! Did you know if your hood can have more degrees? some car just have 2 arms with 2 bolts per arm, in the cars that i see it can be done, if you give more degrees to the hood the windshield will have less ''crash'', also you will have a ''hole'' and there the air will scape from the engine, if you have your grille fully ''blocked'' maybe it will not be so good. Good luck!.

[BamZipPow]

I've pulled the rear belly pan and rear diffuser fer now so I'm only running the rear wheel skirts, rear side skirts, and rear strakes after the main belly pan. So I'll git to see how the rear wheel skirts along with the rear side skirts will do on it's own.

Looks kinda nekkid under the truck now...I can see the rear axle again.

[BamZipPow]

Now this is nekkid! I did notice that the upper part of the rear skirt was really clean!



Reinstalled the rear belly pan and rear diffuser so I can git ready to git on the road.

I extended the rear diffuser with some FRP and a 1"x2" wood strip and set the exit angle of the extended piece to ~10°. I designed it so the exit angle can adjusted as needed.







The revamped support fer the rear wheel skirts. Much cleaner and both upper and lower pieces are supported with individual shelf brackets. I've since trimmed the zip ties and painted the brackets black.

[BamZipPow]

So I have an interesting question...

Since I have built my rear wheel skirts with an upper and a lower panel, what would would likely happen by leaving the upper panel off while driving?

[aerohead]

My library is incomplete,and I've no peer-reviewed research which covers this specific application,so I'm a dead end.Sorry!
I have seen,at least once,a concept car (probably Italian)which had 'skirts',but where 'blisters' might have been,to contain the upper wheel/tire within the wheelhouse,they were left open.No wind tunnel data were given.
I suspect that a nasty 'jet' would be present while driving in rain,making for a dangerous visibility situation for any motorist wishing to pass.
Slower,higher pressure air under the truck would want to escape out the hole,perturbing the airflow right there.

[RiderofBikes]

Originally Posted by aerohead

Slower,higher pressure air under the truck would want to escape out the hole,perturbing the airflow right there.

I think this same thing, not so much about perturbing the airlfow exactly, though that will happen, but more along the lines you'd have obvious unequal air pressures opposites of the panel. Even with your shelving supports are more than enough strength to hold it, I think keeping the two pressures seperated will keep the drag/downforce at minimum, the pressure vent you have following your rear wheels should suffice.

You have to also remember, that closing off the entire wheel well area, you are in turn creating more side surface-area without pressure release through your material that causes you to be affected by crosswinds more.. Think of your skirt as a Sail, No holes means more efficient in catching air and moving, and a Sail with holes... Your open wheel well acts as a Sail with holes. Not to mention theres not alot of contour to the body side-plane and vastly lower Belly pan that prevents that side wind to go under and elleviate pressure that inhances lane drift.