Making a more efficient, aerodynamic soapbox gravity race car

[orengomotors]

The teardrop shape has it's widest section ahead of the midpoint. It's generally a 30/70 split. That means you can sort of bury the front suspension, but the body needs to taper before it gets to the rear wheels, which is a problem.

thank you! i understand it now.

so the nose has to be rounded?
the nissan delta wing nose is poorly designed?

[orengomotors]

some sketches:




is that the final shape?

[orengomotors]

downforce mode on:

[freebeard]

The Nissan delta wing nose is un-necessarily long. If it was blunter you could meet the 16° approach angle with a lower stagnation point.

is that the final shape?

You keep reverting to that high nose. It needs to be like a Porsche 356 with a baby buggy bumper. Or the second picture above.

If you make a single form and fabricate two sides from it, you could fur out the front to get the taper you need.

For the nose, why reinvent the wheel?


Proline Racks: Yakima SkyBox 16,18 and 21 Roof Boxes

These come in three sizes 36" wide by 15-18" tall (914.4x381-457.2mm). I have one of these that's bigger but shorter I bought cheap used. This style is intended for skis. It would need beefed up attachment points and (being thermoplastic) it would explode in a collision.

While I was looking for an illustration, I ran across this:


http://www.akmining.biz/snow/snowcoach_by_equinox.htm

Now this is made of polyethylene and it would be like riding in a big crash helmet.
___________

How much of a boat tail can you squeeze into the rules?
___________

Edit: I see your cross-post. You're putting wings on an open wheel car. If you could figure out how to make a panted, cycle-fendered wheel that created the downforce it would apply directly to the tire's contact patch. I don't know what that would look like.
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Boat tail.

[orengomotors]

Originally Posted by freebeard

You keep reverting to that high nose. It needs to be like a Porsche 356 with a baby buggy bumper. Or the second picture above.

If you make a single form and fabricate two sides from it, you could fur out the front to get the taper you need.

For the nose, why reinvent the wheel?


Proline Racks: Yakima SkyBox 16,18 and 21 Roof Boxes

These come in three sizes 36" wide by 15-18" tall (914.4x381-457.2mm). I have one of these that's bigger but shorter I bought cheap used. This style is intended for skis. It would need beefed up attachment points and (being thermoplastic) it would explode in a collision.

While I was looking for an illustration, I ran across this:


http://www.akmining.biz/snow/snowcoach_by_equinox.htm

Now this is made of polyethylene and it would be like riding in a big crash helmet.
___________

How much of a boat tail can you squeeze into the rules?
___________

Edit: I see your cross-post. You're putting wings on an open wheel car. If you could figure out how to make a panted, cycle-fendered wheel that created the downforce it would apply directly to the tire's contact patch. I don't know what that would look like.
___________

Boat tail.

-ok, i will redo the nose and make it lower.
-you are suggesting to use an existing form? like the sky roof rack box?
-the boat tail is only limited by total body length: 2300mm but also limited by my pickup truck bed . maybe the boat tail can be a separate piece, for making the transport easier.
-Adding wings was just a joke, but what you mean by cycled-fenders?

[orengomotors]

this nose is better?

[freebeard]

Use the roof box directly instead of as a form. Cut the driver position into the back, gusset it appropriately and have 6-8 fasteners to remove it.

You could use a roof box as a boat tail, as well.

Downforce cycle fenders was a joke.

Edit: the nose is better IMHO. Think about a U-shaped clear plastic hatch that hinges open for ingess/egress but fits closely round the helmet just below the eye-slot. If you didn't have the helmet it would knock you teeth out, but the helmet is required. Just make the plastic edge weaker than the helmet.

[orengomotors]

i have already started!

[botsapper]

...use spray foam too.

[freebeard]

Yikes!