Aero Truck Cap Manufacturing
 

I have made another aero truck cap for my Dodge Ram. I am willing to produce these as I see them as a worthy mpg gain.
Now since it's been a while since I've been on here, how do I post pics?

ATCatNorthStarEnterprisesdotbiz

You will need one more post, in order to post pictures.

I am curious as to how your aerocaps look.

Well, I designed it and made it out of .060 Aluminum so it looks squarish. It is functional, has locks and gas springs to hold it open. I am redesigning it to look a bit better. I can design for contractor type caps with the side hatches. It works for me. I get 26-28mpIMPg in a 5500lb 4X4 with a 4.7L.

Blaine

You should now be able to post pictures.

Ok, lets see what happens.

ok, so where'd they go?

I thought I had better pics but you'll get the idea. It also has a cargo light cutout on the front.

B~

What do you mean, as a hobby or as a business?

To be competitive you would need to radius the longitudinal edges, to inhibit vortex formation. If you radius each existing edge to 45° and then flange that, you could have one internally riveted seam. Run the edge roller on a curved edge and it would produce a quasi-compound-curve structure that would fit the lines of the vehicle very well.

You're welcome.

All I would say is, look at the rearward slope and compare it to the template. It actually looks like a good start, and its boxiness might actually be a selling point to those truck owners who otherwise would not consider installing an aerocap onto their truck because it might look "embarassing."

Contractor-type caps as an option would be cool, too.

Thanks for the comments.
The inside has weldable/riveted flanges. I don't care for the boxiness of it but I have a way to make it look a bit better.
I want to do it as a business. Right now it would be built based on orders.

I am also doing hovercrafts made out of aluminum. Welded hulls, flotation foam, four stroke engines. They are more fuel efficient than boats but are not for everybody. My aim is to make them look decent, fuel efficient and much quieter than the old types using two stroke engines.
I built a two seater, two six passengers and am now working on a better four seater.
I spent 13 years as a cnc programmer in the sheetmetal end of a big company so I learned to make some of my own stuff.

Looks nice! I especially like the cutout for the truck's cargo light.

I think that the slope of the top is a bit too fast for the best aero effects, but really any improvement is an improvement, and if your mileage is as good as you say my assessment may be complete hooey.

I agree with the comments about the sharp transitions and the too "fast" looking slope.

For best marketing efforts (and for addressing the skeptics here and everywhere), you'll want to run a well-documented A-B-A test with the cap on & off at a range of speeds to demonstrate its effectiveness.

http://ecomodder.com/forum/showthrea...ery-11445.html

Where in Ontario are you?

I applaud your initiative!

Looks good. I like how it tapers in the plan view.

My old plywood and rubber apparition looked a lot the same. But you have a lid and that makes it much more practical.

I would offer an improvement. Don't carry your cab bulkhead section so far back. 6 inches max. then begin a smooth transition into your slope. Also you can more closely approximate the Hucho template. Also this approximation would leave the back of your slope about 8 inches above the top of the tailgate. While this results in a bigger wake area (bad) the flow stays attached to the slope resulting in less drag. Bondo made his beautiful fiberglass top that way and in the wind tunnel the smoke stuck to the lid all the way to the end. A higher rear lip allows the owner a wider array of freight - always important to pickup guys.

Get with Phil Knox (aka aerohead). He's forgotten more about pickup truck aerodynamics than most of us on this board will ever know. His crazy (but probably effective) ideas scream out for somebody with the manufacturing smarts your work evinces.

Depending on material costs, you design looks economical. Maybe you could even design it to be molded out of ABS. ABS commits you to high-volume tooling. The stuff is not easy to fabricate, but makes a good product. That's why it dominates in automotive accessory bodywork.

Definitely talk with Phil, but not for a while - he's working night and day getting ready to take his truck to a wind tunnel in a couple of weeks :eek:.

The idea of the bulkhead section being a bit long is;
1. contractor-type hatches on the side for storage of tools.
2. that is where I'd change the size for different lengths of truck boxes, keeping the slope the same. Mine is a 76", there is a 67" and then the 96"
3. didn't want such a long lid due to the winter season, loading snow, getting too heavy.

I will be doing another when I get the cash and be selling this prototype.

I have a scangage but it isn't set up properly. It's reading too low. Tank to tank fillup was showing the 26 - 28mpIMPg. I gotta reset the gage but don't know how.
I was in Michigan when I bought the truck in March. I changed the oil to Amsoil. Then I moved to Canada. Now it has Mobil1 synthetic in it. Now the truck cap so I don't have a proper base mileage. I was originally going with the scangage numbers but that has proven wrong. I took a two day trip to Nova Scotia. That is when I did the tank to tank mpg check.

Tank to tank testing isn't ideal.

If you want to be able to convince skeptics, read up on A-B-A testing (including coast-down tests). You need to remove as many variables as possible so you have high confidence the changes you see are just from the cap.

When you fill up select the menu by pressing the button outlined in red on the lower right, press "more", press "fillup", press the more or less arrows until it matches the amount of fuel you have used and press "done". It learns to more closely match real world mileage if you do this every fillup. Be patient, it may take a while. However, for A,B,A testing it may not have to be perfectly calibrated. We are more interested in a percent of change than mpg. For example, 3 mpg may not mean as much in my car as it would in a big work truck.