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Old 04-29-2013, 08:32 AM   #1 (permalink)
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Forester boattail

I just posted a picture of a Forester on the Template. Since the roof angles upward, the back is the highest point, requiring an absurdly long boat tail, but I realized that it was irrelevant to the bottom half, so here is a version with a line parallel to the original, but actually going from my bumper:

Here is one mirroring the Template top, but shifting it forward:

As I understand, the template bottom is not expected to maintain attachment, it is just designed to not hit anything. The red line is the same angle, going up from where my wheels touch the ground, so if this theoretical boattail ever hit anything, it would have gotten too close!

Now I know what I want to do with my life! :P

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Old 04-29-2013, 08:38 AM   #2 (permalink)
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Now we're talking

My '98 is the same generation as yours.

Before I dig into a big project like a tail - which would be nice, considering since I got a new transmission my Fozzie struggles to break 22mpg highway - I'm going to make some rear wheel skirts and add some smoothies on the wheels all around. Low hanging fruit first.

Take the roof rack's crossbars off. I did. My wife fussed at me, saying they should stay on the car, but I pointed out that in the 11 years we've owned the car I've only put cargo on the roof once, so it isn't a big handicap.
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Old 04-29-2013, 08:40 AM   #3 (permalink)
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Don't forget side taper

You don't get to bring the profile in much from the top, but don't forget the plan view. The Fozzie is pretty slab-sided, you should be able to start bringing in the sides right there at the taillights.
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Old 04-29-2013, 10:16 AM   #4 (permalink)
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Quote:
Originally Posted by elhigh View Post
My '98 is the same generation as yours.

Before I dig into a big project like a tail - which would be nice, considering since I got a new transmission my Fozzie struggles to break 22mpg highway - I'm going to make some rear wheel skirts and add some smoothies on the wheels all around. Low hanging fruit first.

Take the roof rack's crossbars off. I did. My wife fussed at me, saying they should stay on the car, but I pointed out that in the 11 years we've owned the car I've only put cargo on the roof once, so it isn't a big handicap.

Don't forget side taper
You don't get to bring the profile in much from the top, but don't forget the plan view. The Fozzie is pretty slab-sided, you should be able to start bringing in the sides right there at the taillights.
Oh yes, I would definitely taper the sides. It would get the same taper as the bottom.

The crossbars are sitting right next to me. I removed those as soon as I had the right screwdriver!

I had thought that if you made rear wheel skirts, you might as well make them lower and integrate boat tails on those.

I guess that mud flaps would be superfluous afterwards.
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Old 04-29-2013, 10:19 AM   #5 (permalink)
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I'd take the entire roof rack assembly off, if the bolts are external (some are horrible to remove from the inside, requiring you to get under the headliner).

Removing the crossbars is a start, but we rarely drive in no wind or in a true head/tail wind, so the impact of the side portion of the racks is bigger than their small frontal area might suggest viewed from head-on. In a crosswind, their effective frontal area is significant.
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Old 04-29-2013, 02:33 PM   #6 (permalink)
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These require removing the headliner and then I would need to plug holes.

Personally, I like having the headliner lining my head...

Sawzall?
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Old 04-30-2013, 04:17 PM   #7 (permalink)
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tail

I'd maintain the upper curvature as you have it,but for the lower,it will depend on where you begin your diffuser.So it's angle will be 2.5-degrees,or around 4-degrees depending,and you can ignore the red line since you have so much ground clearance to begin with.
You may want to do it in 'installments',to see how you like parking 'n such.If you think you can live with more length then go for it.
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Old 04-30-2013, 05:50 PM   #8 (permalink)
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I think what you want to do is a version of Stuntbusters AeroJeep.
http://ecomodder.com/forum/showthrea...eep-21160.html


It looks reasonable to live with. Also your Boat tail will be shorter than your picture. Since your car is taller than it is wide, you'll end up with a Fishtail that'll terminate before the top and bottom are able to reach each other.
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Old 05-16-2013, 03:29 PM   #9 (permalink)
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For anyone else who had not seen that thread: http://ecomodder.com/forum/showthrea...eep-21160.html

(Sheepdog44 actually linked this above the video)

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Old 06-12-2013, 06:21 PM   #10 (permalink)
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Jeep

Quote:
Originally Posted by Xist View Post
For anyone else who had not seen that thread: http://ecomodder.com/forum/showthrea...eep-21160.html
In 1932,Oskar Tietgens and an assistant at Westinghouse Laboratories kinda did the same thing to a self-propelled railroad car.
They published Cd 0.08 for their creation.These early numbers may be taken with a grain of salt,as Hucho cautions,but are interesting nonetheless.
Love the 'Jeep.'

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