F-250 7.3 4wd Light AeroCap
 

Did my initial structure/mpg test on my light weight aero cap made of EMT conduit and 4mil plastic sheeting. No significant flapping and cursory +3 MPG on scan guage.

http://ecomodder.com/forum/attachmen...p;d=1268270122

More photos below.

Want Pictures!
 

:thumbup:

Do I put them here or another thread, relative noob here. I took build up shots. And have vid of the test.

This thread if fine if you don't have another build thread.

Light Weight AeroCap F-250
 

Light Weight AeroCap F-250
Near Final result

bajascoob, great work, looks nice and you see out of it,
3 mpg, wow that is wonderful
pls share how you constructed it, any pic of the inside.

where in omaha are you in? my cuz is in 112th and center, I went to unl

Light Weight AeroCap F-250
 

materials
7 lengths 1/2" emt conduit
1 -1/2 coupler (1/2")
2 - 1/2 conduit 90* elbows
5- 1/2 emt hold down brackets
desired hardeware (1/4" nut and bolts)
bag of 3/4" hose clamps
8- 1/2" L brackets
4mil plastic sheeting (paint dep), 6mil would be better but only came in 100ft lengths
roll packing tape
2 rolls transparent duct tape
6- 1/2" wrap around foam insulation sleeves (comes in 3ft lengths?)

tools
conduit bender
nut driver(to fit hose clamps)
screwdriver
welder(optional)
scissors

Bend B pillar arch..(tip-bend one side, measure to center cab, mark center cab length on arch, trace half arch on floor, flip emt, align mark, bend to match trace)

attach 90 elbows between base of b-pillar arch and bed rail conduit.

bend bed rail lengths over tailgate, apx 2" over hang tailgate. tail gate lengths will overlap, cut both somewhere in overlap, allow 1/4" gap for coupler, install coupler.

check for fit.

install arch crossbrace with L brackets and hose clamps

check fit, adjust tailgate coupler if needed

install down bars with hose clamps and L brackets, note aero angle. Permanent mount upper bracket, temp lower/tailgate and do not cut to length yet.

side braces are under tension, make long enough to bow down bars up(note will lean in until down bar brace is in)
side braces-flatten emt ends in vice or hammer bend over to appropriate angle to fit hose clamp on down bar

cut down bar "tails" to length and perm install

install down bar cross brace with brackets and clamps, make length to desired horizontal bow/curve.

make sure all hose clamps are positioned so sharp edges are inward(away from plastic)

Check fit

install 1/2 emt hold down brackets(drill/bolt)-my design has passenger side semi-perm installed and act as hinge(need to be inline for hinge to work well)

Driver side quick disconnect- ran bolts up from bottom, bolted to bed with threads sticking up so emt clamps fit over them.

I wanted to install the quick pin release for all driver side mounts but the angle of the sheeting did not allow for my design. For the quick release I made an F channel by welding strap to angle iron.

I installed the plastic over the top and sides and temp taped with clear packing tape, stretching the best I could, then used the transparent duct tape along the entire edge apx 6" over the emt seemed to work well, all taping done inside the cap.

I then covered the arch face, taping having to be done on the outside.

I put a layer of duct tap on the edges that touch the bed rail to protect from abrasion.

I was considering how to prevent abrasion from the down bars..I had some left over pipe insulation and squeezed it around the down bars and down bar cross brace, which had the added benefit of tightening the plastic more.

I also put the insulation on the arch cross base to pad and space the cap from the cab.

I tack welded some of the emt connections for extra strength( don't breath fumes)

When putting on the duct tape I used two widths.

There is noticeable increase in mileage, and actually noise reduction.

I drove with it 2200 miles on a trip. the only wear is on the tailgate edge overhang, water got under the tape through openings where the down bars meet. I drove through 1700 miles of rain and snow during this trip. Another layer of tape and close off the gaps I think will help.

The overhang was slightly bigger than planned but an unplanned benefit is I can open the tailgate with out lifting the cap, and I think there is a little air pressure that gets into the cap and keeps it from flapping.

The kamback is not perfect but it was easier to design this way, and some is better than none.

I wanted to fold my mirrors in but during the day the cap is not clear enough..at night you can see the headlights.

The FL sun did loosen it slightly but it still doesnt flap. I may do yarn tests later if the weather cooperates.

Thanks for the pictures.

So what kind of fuel improvements have you seen?

According to my truck computer about +3-4mpg highway and +2mpg city. I have to go through my receipts from this trip and do some cipherin'. I have a scan guage but I was doing random/partial fills to take advantage of best fuel price (St Joseph, MO, walmart)

great #s Baja,

Any new mileage data?

i like that you can see through it.

I still haven't got a chance to get a good ABA. Between the scanguage and the truck computer it's 3 or more mpg on the HWY. I recently change the plastic material to "3M 2174W Outdoor Patio Door Insulator Kit with Tape Dispense" and welded the emt, removed the hose clamps. I was able to use only one box of the 3m stuff with some creative cutting. This stuff has no rip-stop but it is nearly invisible. Pictures to come.
Amazon.com: 3M 2174W Outdoor Patio Door Insulator Kit with Tape Dispense

How well can you see through the new material? could you post a picture or two?

Thanks

Light weigth aerocap
 

Here is the 3m version. it is perfectly clear. it lasted for a good while untill i hit it with my daughters scooter, unloading. it cut it. I taped it, which held for about 200miles.

Found some non-3m film that is a bit thicker, and on sale (early spring clearance of winter stuff). I wasn't really happy with the bed mounts before so I redesigned them, for easier access/install/removal. I double nutted the bolts in the be rail, so the nut and bolt always stays, and I just have to put the top nut on to install. I welded hinges in place of the clamps. On the driver side I removed the hinge pins and replaced them with "hair pin" for quick tilt up access. The "sliding glass door" size isn't big enough so I seamed it with the included tape. Previously I left triangle seams, this time I'm living on the edge and went straight across the back, it's a bit cleaner this way.

Very Nice! So what are you MPG numbers up to now with the +3mpg?

My dad has an '02 F250 7.3 4wd and averages right at 20 mpg with a moderate "tow" tune adding ~75hp and 125 ft-lb torque...of course I couldn't get him to do this because no ATVs or goosnecks could go in the bed...lol

went from 16 to 19 on the highway. I run grill inserts too, lund makes some for winter warm up that clip in, I leave them in all year, unless I'm towin across the desert, then I take two panels out. I reviewed the eff mods list again and I may make some more grill area adjustments.

"wind tunnell" testing
 

I like the video, looks like it will work very well.

I have the exact same cab configuration as you and I was wondering if you had some closer/larger shots of it installed and how its mounted? How much total was all of that conduit? I have contractor pricing on homebuilding materials but I've never purchased it before. Would you be interesting in building one and sending it to me in parts?

1/2 " EMT is pretty cheap. Even if I cut it up a little, it would be a long box :) I wonder If I just built the "intersections" then a person could cut straight pieces to match their bed size? I guess the only angle that would change would be the down bar to top of tailgate, and I could make that adjustable.

right now the EMT is 1.69 at Lowes. Takes 7 "sticks" to make this so..$11.83

:thumbup:

I should have done some research, this stuff is cheap, haha so even if I mess up it wouldn't be an expensive mistake. Thanks for the heads up, for some reason I had figured it would be much more expensive. Do you happen to have any larger close up pics? Mostly of the crossmember and where/how they tie in? This is of course unless you want to remain unique with your design! Haha thanks a lot for the information again.

Nice definitely headed this direction when i get around to the s10 eco build

Hello, is this still on the truck, and if so how has it held up with this configuration in the past two years?