Do these "spoilers" really help???
 

Hello all,

I found these pics online the other day and wondered if they had any merit or not. I just can't afford my re-designed bed cover yet as I haven't gotten back to work, but was trying to find a way to use the old cover in the mean time. I have never uploaded pics here so I hope this works.

The first two are what I am thinking about trying until work gets better. The last one is just plain silly in my untrained eyes. I would think the last pic would just make a bigger "hole" behind the truck.

I hope these are big enough to see.

Thanks.

I think you'd be far better off with one of those tonneau covers. This looks like it will produce drag for the sake of downforce. The side ones perhaps help stability (?) but would also produce drag I think.

You'd rather keep the slow air bubble in the bed so the faster air flows over it.

1 and 2 look like they'll make it easier for the air in the bubble to flow out of the bed.

Why not make your own cover out of cheap / leftover material ?
Even covering just the rear half or so will help (it's even patented ;) )

Yeah, they look like they'll increase the area / wake.

Maybe some ramps to aid the trapped vortex instead:

http://ecomodder.com/forum/attachmen...7&d=1290786118

scam
 

My opinion is that this is a scam.The US Patent Office WILL issue patents for worthless s---.I believe that this is what is represented in the 'design'.
Too much has been investigated with respect to pickup truck aerodynamics to believe the airflow depicted in the graphic could ever occur.
As of 1981,Ford Motor Co. knew that as little as 10-inches of plywood,placed across the bed rails,in front of the tailgate,would show a mpg improvemet at the pump.
The quickest and cheapest thing you could do for fuel economy is to cover the back half of the bed only.Any way you can do it.

A plywood and 2x2 framed Kammback should be easy to make, have it hinged so you can open it, like a hatch back.
Its the best choice out there, I think...:D

The first two images as already pointed out would disrupt the stability of the dead air pocket in the bed.

The last one is as silly as you think it is.

The point made about valueless patents being issued is a very good one.

Show us the cover, the truck and frame pieces you still have. I'm sure a second set of eyes on the problem will help.

Bump,

Has anyone tried this? Im curious what a kamm on the tailgate of a truck would / should look like.

Tru, I think the Kamm would go behind the cab...not on the tailgate. Just my guess.

Well - - - - -
The Kamm would start at the back of the cab roof (more or less) and go down and back to the top of the tailgate. Ideally, it would be gradual curve, as opposed to a straight angle back and downwards.

I know there are some threads in the Aerodynamics section here where people built what we're talking about, for trucks.

Done right, it would help the truck body take on the shape of the ideal "template" curve. See this thread for the template: http://ecomodder.com/forum/showthrea...rt-c-9287.html

Having learned a bit about using the template, I can say that one important point is finding the right height that the new bed cover needs to arrive at, at the rear of the truck. Depending on the existing truck shape + the length of the bed, it might need to end higher than the top of the tailgate - or not. If it slopes down at too steep an angle, the air won't flow along the panel, instead it will break away with resulting turbulence.

You want to coax the air to follow your new panel downwards, and then depart from it with the smallest cross section of wake you can get. Basjoos did it on the aerocivic by building an extended tail that tapers down to a panel just big enough to hold the license plate and required lights. On a truck you can hopefully taper it down to the size of the tailgate - but only if the bed is long enough to build that taper with a shallow angle or curved line.