11-13-2015, 01:31 PM
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#121 (permalink)
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Lean Burn Cruiser!
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Lowest Cd without boat-tail?
Hey y'all, it's about time that I dig this thread up!
I have been thinking quite a bit about the ZX2's aero lately. While the boat-tail is the big kahuna, I am curious to how low the Cd can go without having one.
The Ford Probe 4 is a source of inspiration for one mod.
This says a 5% reduction in drag, which would mean my car going from 0.269 to 0.256.
I wonder if the Cd can get close to 0.20 with no boat-tail and further optimization of the aero mods I already have plus some more...
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11-13-2015, 02:42 PM
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#122 (permalink)
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Master EcoModder
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That 5% on that (3/8 scale) body in that wind tunnel. You'll never know when you reach 0.20 without a wind tunnel. But—aerohead's done it.
Basjoos' Aerocivic has double wall skirts between the front and rear wheels.
I used to think the best replacement for a physical boat tail would be actively blown Coanda nozzles. But the big contender today is Plasma Actuators.
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11-13-2015, 03:29 PM
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#123 (permalink)
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Not Doug
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Why weren't the strakes in front of the rear tires as good as those in front?
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11-13-2015, 05:48 PM
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#124 (permalink)
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Lean Burn Cruiser!
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Freebeard - Coastdown testing would give me a close approximation to what the actual wind tunnel-verified Cd would be. When I do work on the area around the tires, I think I will copy the Probe 4 for the front and rear of the tires, while having the Basjoos double skirts in between. Seems like I read somewhere that Basjoos's design is about the best it can be. Aerohead said it, IIRC.
Xist - I think that it had to be more gradual for speed bumps and the like. While it was a prototype, I still would think the designers attempted to make it at least somewhat road worthy. That's my guess though  |
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11-13-2015, 08:43 PM
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#125 (permalink)
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Master EcoModder
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Here's something I made in March,2013, for a pickup truck.
Two U-shaped pieces. Metal angle iron to hold the shape and allow for mounting. And conveyor belting that is fastened along the sides but [possibly] not across the end to allow the belting to flex and rebound.
The metal bracket could easily be V-shaped as well. Or A-shaped with an internal brace. |
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11-14-2015, 03:55 PM
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#126 (permalink)
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Master EcoModder
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Probe-IV
Here is the Cd 0.152 configuration,relying on active front spoiler and active suspension to drop the nose and raise the tail.
Here you can see the 'urban' setup and 'highway' setup.You'd want to do both as Ford did.
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11-16-2015, 01:06 PM
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#127 (permalink)
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Master EcoModder
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I had the idea recently that traffic cones might be a really good material to use for this. They're already molded into a fairly usable shape and they can take a serious beating!
Just a thought...
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11-17-2015, 07:11 PM
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#128 (permalink)
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Lean Burn Cruiser!
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All great ideas! I'm not going to be able to do the active suspension, as an active air suspension for my car is between $1000-$2000  So all I can do is go as low as possible, probably around 3" lower than it is right now. Unless I strike it rich, which is highly unlikely 
Awesome sauce in regards to the tire fairings. I've got ideas tangenting from y'alls ideas, and they should work given enough R&D.
Big news! I did tuft testing today  Here is the video and link to the thread I started just for it.
http://ecomodder.com/forum/showthrea...tml#post499703 |
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11-18-2015, 01:47 AM
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#129 (permalink)
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Master EcoModder
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Good for you, but a chase car or a selfie stick out the window would reveal more.
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11-18-2015, 08:04 AM
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#130 (permalink)
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Lean Burn Cruiser!
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Quote:
Originally Posted by freebeard
Good for you, but a chase car or a selfie stick out the window would reveal more.
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You're right freebeard. I'm hoping to figure something out so we can get a better view of the rear. My brother didn't want to drive yesterday, he said it was a waste of gas lol.
What are your thoughts, judging by what you can see?
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