T-100 side skirts and belly pan...
 

My belly pan thread...
Under belly pan... - Toyota Nation Forum : Toyota Car and Truck Forums

Finally made some time to address the side skirts and move away from the Coroplast which has held up quite well fer the beating they've taken. The tractor trailers that have side skirting uses something similar to FRP. ;)

Cut the new side skirts from FRP and lined everything up so it would look a little more even than the Coroplast setup. I'll have to find some time to clean them up after it stops raining and then I can start painting it black, too. :D

The back edge overlaps the rear wheel skirts by 2". ;)

http://i677.photobucket.com/albums/v...s/IMG_2065.jpg

I'll eventually git some rubber conveyor belt strips to line the bottom part of the side skirts and see what that does. :D

The side skirts are supported on the backside with a metal wall stud and blocks of wood at the bolt on points to keep it tight up against my belly pan crossbeam supports. Two 5/16" bolts keep the side skirts in place and takes less than 15 seconds per side to remove using my electric impact wrench. :D

Current view of the bottom of the truck before the side skirts were replaced... ;)
http://i677.photobucket.com/albums/v...s/IMG_1976.jpg

That belly pan is awesome!

Looks good. How much improvement in mpg?

love it!!

Well...not exactly sure how much the side skirts on their own contribute to my gas mileage. Haven't played around with the height of the side skirts yet...maybe that might be something to look at once I git the conveyor belt material in. :D

I've entered my fuel data and the various mods from the first day I got my current T-100. I've separated out each years worth so you can see which direction I've gone so far... ;)
1998 Toyota T-100 SR5 Gas Mileage (BZP T-100 current (2013)) - EcoModder.com

As a quick project, have you played with the idea of losing the skirts and trying controlling the airflow around the tires?

I can't speak for your truck, but controlling airflow in the wheel arches and around the tire seems to be a much bigger deal.

What do you think?

Are you suggesting that I pull various pieces off and see what happens or pull everything off except fer the rear wheel skirts? :confused:

The side skirts keep the air between the belly pan and the bottom of the truck from bleeding out. My belly pan is a dropped belly pan method. There is about a 5" gap between the bottom of the truck and the top of the belly pan.

If I pull the aero cap, all the belly pans, rear diffuser, side skirts, and crossbeam supports...should I keep the rear wheel strakes in place or pull those as well?? Do I need to put the front air dam back up to the stock position? If I do that, then I'll need to pull the front air dam belly pan as well. It would take me about an hour to pull everything but a good day to put everything back in place. Not sure I want to go through all that just to see what the rear wheel skirts will do on it's own... ;)

The way I see it, and this is only my humble opinion, side skirts seem to work because of the side effect of controlling air hitting the rear tire. Look at how your skirt hits the rear tire.

The air under your truck is 95% passing air and 5% cooling air, which is contracting as it loses heat. For this reason as much as any other you have a low pressure area under the truck, and this increases the depth of the low pressure area behind your truck. Great for handling, doesn't really help with reducing the cd behind your truck.

If you have a full belly pan, so air under your truck is not an issue, directing air around the rear wheels is a win, and it would be worth a good ABA test to see if it helps to put thait air outside the truck, or inside, under the bed.

I suspect that if you put that air under the truck instead of outside, it would have a smooth ride under your belly pan for about 30" then help reduce that low pressure area behind your tailgate.

If you look me up, you'll see I am on a similar path you you. I plan to do ABA testing to see what happens with these options... It would be a good heads up if you did the same :)

:thumbup:

Here's what my T-100 looks like without the side skirt... ;)
http://i677.photobucket.com/albums/v...s/IMG_2069.jpg