Finally Got Side Skirts
 

I finally got side skirts to work with my air dam to keep high-speed air from getting under the truck.

I used the factory running boards with an aluminum Z-section to attach rip-stop conveyor belting. Ground clearance: 1.5 inches.

It does need some finishing work (paint and fairing the wheels) but I can start testing tomorrow.

No pix yet. I have taken them but the site gallery has some sort of problem with them.

I'm eager to see these. As a Jeep owner who is just getting started on the hypermiling habit, I'm most interested in the things people who own larger vehicles do to improve their efficiency. Especially when they are getting 25+ mpg out of an F-350 :thumbup:

Are the pictures above the upload limit for the site? If so, you can email them to me (benjamin.jones@ecomodder.com) and I'll host them for you.

I'll send e-mails shortly.

I'm in the middle of changing my ISP.

First tankful in using air dam & side skirts. 27.25 MPG with heavy use of A/C.

I view the side skirts as part of the air dam.

Prior to air dam/side skirts I was knocking around 26.6. Gimme a couple more tanks to stabilize out.

Definitely a gain though! This is something to do with my Jeep for sure. Question though, do you feel you don't have adequate clearance or angle of attack with the low ground clearance (1.5")?

Nice! :cool: And the A/C is probably cycled full-time in this heat, making the improvement more impressive!

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http://www.azclubgp.com/images/smiles/ttiwwp.jpg
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Got some results.

Before air dam & side skirts:
Over1096 miles -26.27 MPG

With air dams and side skirts:
Over 1100 miles - 26,99 MPG

Improvement: 0.72 MPG = 2.7%

This is high summer on the scorched steppes so lots of A/C.

One more tank of normal circuit then a road trip to Nashville for single shot injectors.

Pics should be up soon.

Pics were never posted here, but are there pics of this truck anywhere else maybe?

Thanks :)

well, he just posted yesterday so at least hes still here

No pics. Got rid of the side skirts.

More trouble than they were worth.

Were they scraping the ground too much?

I was behind a lowered pickup the other day that couldn't have been more than 3 inches off the ground (most likely not for the aero benefit), going through a town where they were completely redoing all the roads. He was going about 5MPH trying to avoid scraping his truck through the dips in the road, and actually had to go through a gas station to avoid a major dip on the way. I guess lowering too much would just get annoying after a while.

Chaparral built a racecar called the 2J. It was known for having a snowmobile engine on the back that sucked air out from under the car for increased downforce. Less recognized is that, in order for that to work, the ground clearance had to be as small as possible. They came up with side skirts that moved vertically in opposition to the suspension movement with a system of cables and bell cranks. Whether that can be adapted to a road car with long term durability remains to be seen, but it might be something to consider. It's something I've thought of trying, but the complication, maintenance, and weight don't seem worth the effort to me. Thought I'd throw that out there anyway.

Violates the K.I.S.S. principle.

Yeah, that's partly why the car seldom finished a race before it was banned.

I gave them 2 inches clearance, but that was just enough to occasionally drag. They eventuallt tore off the clamp at the front wheel. They were made of 3/8" ripstop conveyor belt. They helped about a quarter of one MPG.