Gurney Flap on a Pick-Up Truck

[kach22i]

This thread is a "how to" on what NOT to do if you want to save gas.

Link:
Rear Spoiler on Pick Up Truck - Experiment - Pelican Parts Technical BBS

This modification will cost you gas, although it will add some tracking stability on the highway which I like very much.

The crazy version:
Rear Spoiler on Pick Up Truck - Experiment - Pelican Parts Technical BBS


How it is today:
Rear Spoiler on Pick Up Truck - Experiment - Page 2 - Pelican Parts Technical BBS



The flip down hinge I installed two years ago has since rusted to a set angle. Should anyone do this, use stainless steel piano hinge from a boat supply store.

The shorter Gurney flap will cost you about 1 mpg on the highway, but I like the added stability at highway speeds so it's staying.

In Michigan we get black ice, and after a night of that pick-up trucks can be found in the trenches off the highway and in the grassy/snowy divided highway area. For this reason I'm keeping my Gurney Flap, it's a safety feature at this point. And like most safety features it costs a little in gas mileage.

EDIT: The full photo album on this truck link.................
S10 4x4 Pick Up pictures by kach22i - Photobucket

Sample:


Yes, I also own and experiment on my hovercraft.

[sid]

I used to have a hovercraft, which I built. More info on it can be found at stonemarmot.com/rants » Sid’s Hovercraft (Data) and blog pages adjacent to this link. I did a lot of experimenting with my craft.

[Frank Lee]

That ain't no Gurney flap.

[Joenavy85]

1-2% of the airfoil chord, set at a right angle to the pressure side of the airfoil. You have no airfoil, and therefore no Gurney Flap.

[kach22i]

Originally Posted by sid

I used to have a hovercraft, which I built.

I think I've seen your hovercraft before. Maybe in person, or just on the Internet. I post at hovercraftofamerica.org sometimes.

I see that I have the same engine you used to have.

35 hp Cuyuna ULII-02 two cycle, 2 cylinder ultralight aircraft engine, electric start, weight 79 lb.

Would you by any chance know if there are headstud bolts or other type bolts on the bottom of the engine which require periodic torquing or tightening down?

I've done the top part, but the base support plate is in the way of the bottom, and I don't know what is under there.

Link to my experiment in progress (semi-disaster now that the foam is water logged):
Hovercraft - Experimental Skirt Project - Boat Design Forums

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RE: Gurney Flap

I understand that in a strict sense it must be attached to a wing, not a rear deck - thank you for the correction. I just want to point out that I'm not alone in stretching the definition.

Gurney flap - Wikipedia, the free encyclopedia

The Gurney flap has also been implemented on the rear spoiler of the 2010-2011 Shelby Mustang GT500.

2010 Ford Mustang Shelby GT500 - Gallery
2010 Ford Mustang Shelby GT500 rear spoiler Photo Car and Driver - (305268)


I'll just call it a rear spoiler next time.

[Frank Lee]

You do see that raised lip on the Mustang, and lack of same on yours right?

[kach22i]

Originally Posted by Frank Lee

You do see that raised lip on the Mustang, and lack of same on yours right?

Dear Frank,

The difference I see is that mine is a whole lot taller.

What do you see?

Cheers, George/kach22i

[Christ]

Look at the spiller on the mustang.... Then notice the black thing at it's edge, which is a gurney flap.

You have nothing more than a spoiler.

[Frank Lee]

Originally Posted by kach22i

Dear Frank,

The difference I see is that mine is a whole lot taller.

What do you see?

Cheers, George/kach22i

I think you are going to need more help with this than I can give.

Good luck.

[AeroModder]

The lip on the Mustang spoiler looks like it would be more cosmetic. If I'm not mistaken, the Gurney flap's purpose is to assist the flow of air under a wing, keeping airflow attached at higher angles of attack.



There's just dead air under the Mustang's spoiler there.