Brain Tsunami- Tail extension

[UltArc]

So the tail extension is nothing new or miraculous-

-but me making one that looks good, is.

I bought a bike rake from Goodwill for $5, and was going to make a janky polycarbonate/metal one for the GGP- but why don't I just do it right?

I am going out now to make a pc design, and then construct out of fiber glass. Will post images shortly after start.

[sheepdog 44]

All the way! Don't stop at 2, 3, or 4 feet. Make it 100% in length to the template. There's no point going halfway and calling it good enough, when the other half is just full of MAGICAL aerodynamic properties unknown to daydreamers like me, ineffably described as "downhill both ways."

[UltArc]

Figured out the right angle, I was going to just make it flow with the body of the car shape wise, but I am going to look at some measurements for construction.

Just got home from Menards with 25 square feet of fiberglass cloth, two paint brushes, and some spray bed liner. Researching dimensions now, would like to at least get one portion done tonight.

[UltArc]

Work station:


My first section (will be center piece):


Still looking into the exact dimensions I want, I am having trouble finding anything I can comprehend on here- or even searching for the specific term.

All advice, direction, and math help given will be appreciated

[Xist]

Your bike rack is way more appropriate than mine! I am not even sure how to redesign mine to stay within the template!

Hurry up and be awesome!

[UltArc]

What does it look like?

I was hoping Aerohead would chime in, or someone else who has experience with their design, or with the physics behind it. I saw a few equations about, but didn't comprehend any.

Also, my fiberglass sucks. It turned out terrible. Sturdy when securing it to another[piece of fiberglass], but my method does not make a nice solid and sturdy piece to make a wing from, so I either need to make a frame (a lot of PVC around) or use polycarbonate and just make it look nice, or wrap it in fiberglass.

If I don't hear back, I think I will just make it from polycarbonate and lower my looks expectation.

[freebeard]

All the way! Don't stop at 2, 3, or 4 feet. Make it 100% in length to the template...ineffably described as...

...diminishing returns.

Still looking into the exact dimensions I want, I am having trouble finding anything I can comprehend on here- or even searching for the specific term.

All advice, direction, and math help given will be appreciated

How about opinion?

Is it the finding or comprehension? "mustang boattail" finds 739 results. "mustang boat tail" finds 4,900. The problem is it sweeps up every post that has 'Mustang' in anyone's profile. I'm not going to look at all of them.

A proper boattail would include the roofline. Have you thought about the tailights and license plate? How big a bustle are you willing to drag around? You could do a lot with an 18" extension including a partial bellypan/difusser.



You're 'b' so ~4°.







A box cavity or base plate would involve less fabrication.

Bonnevile spoiler:


A rigid piece of fiberglass will have maybe 6-8 plys. I'd eschew PVC and polycarbonate. Look for Polymetal, Alumipanel or MaxMetal (Same thing with different brand names). It's plastic with aluminum skins. I pick up scraps at the local recyler for experimentation, but I don't have any pics to show. The 3mm stuff can be sheared, rolled and flanged by hand, and its about as strong as 5/8" plywood at 1/10th the weight.

[UltArc]

BASE PLATE.

That's what I think I am doing. This is not a boat tail, rather a rear fin- there are probably all those boat/tail results because of Insight boat tail and my comments on others with my signature/garage auto inserted.

This project and my Insight front wheel skirts are taking a back seat because of the next thread I post.

EDIT:
My inspiration:




From: http://ecomodder.com/forum/showthrea...tml#post384969

Which led to:



The whole thing is here, but a lot of mods were done at the same time: http://ecomodder.com/forum/showthrea...tml#post393658

[freebeard]

I remember that New Beetle. The Cd went from higher to lower than stock.

I would call yours a Bonneville spoiler—0° angle for mimimum downforce. It provides a surface for turbulence/vortexes to reattach to. How did it compare to the 2nd iteration?

The base plate, as shown, is a vertical section of the template. I could easily do one with my bike rack. It looks like this:



It would be easy enough, but without instrumentation I would be trusting the seat of my pants.

[UltArc]

I have instrumentation, and the big difference in acceleration and coasting inspired me to do a boat tail on the Insight. The modification has to look good, and I want it completed before the GGP- ruling out the boat tail.

You are dead on, regarding what I want to do. My question for the experts here is this: What are the optimum dimensions? I don't expect people to research my car, and build it for me, but if one could direct me to a source to learn on, or advise equations to calculate, that would really be appreciated. Extensive searching has shown me LITTLE on how to do this myself; it's all either a product, beyond my comprehension, or something completely abstract from my purpose.