03-24-2013, 10:37 PM
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#21 (permalink)
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Master EcoModder
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Ideally, the trike would be FWD, with a 300 mile range and a 144 volt system capable of 180 mph and weigh only 500 pounds and fit 4 passengers. You have to stop things some where unfortunately.
If I make it electric, and in my budget, I'd have a 20 mile range. So then aerodynamic efficiency doesn't matter and that kind of ruins the whole idea of my build. If I'm building a vehicle that gets 150 MPG, I should be able to go more than 20 miles because then what's the point?
I'm currently conflicted...
I think I need to sleep on it. Lots to think about.
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Currently driving a mostly stock 2014 Mitsubishi Mirage DE hatchback.
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03-24-2013, 10:54 PM
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#22 (permalink)
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Master EcoModder
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Remarkable achievement for a young man. At your age my dream was a human powered aircraft. At 62 now I never achieved that dream but you can see human powered aircraft in the Smithsonian Air and Space Museum. I would still like to build one but I think the best way would be an inflatable in a sailpalne configuration using helium so it would actually be practically weight neutral itself.
I have chased another dream which I hope soon will become a reality.
regards
Mech
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03-24-2013, 11:22 PM
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#23 (permalink)
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Master EcoModder
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The more I've been thinking, the more I'm turning towards chopping my recently acquired geo metro up and making that thing a trike. it already needs paint, an engine, and a gas tank, so it makes good sense...
Similar to
http://ecomodder.com/forum/showthrea...ect-22635.html
It's more in my price range, and gives me a vehicle that I could actually drive everyday...
It's safe to say I'm indecisive...
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Currently driving a mostly stock 2014 Mitsubishi Mirage DE hatchback.
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03-25-2013, 03:39 PM
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#24 (permalink)
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Master EcoModder
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I'm going to be taking this project into the direction of something a little different:
I came up with this idea a while ago, but now I'm putting the plan into action.
The only modification is I may not be doing is a top chop because it would only result in a slight difference in drag and is a huge amount of work. Taking the mirrors off would have about the same result and that takes 15 minutes vs 2 weeks. so hopefully you're getting my point.
Anyway, I'm shooting for 100 MPG while cruising at 60 mph.
Mods Include: - Turning vehicle into a 3 wheeler
- Full Streamlining
- Video mirrors
- Engine rebuild with fuel economy in mind
- Tallest Transmission available(if I can find one. I currently have the 3.79 but the 3.52 ratio would be even better)
- Tall and skinny tires
- Suspension lowering
- Fully ducted cooling system
am I missing anything? haha. Basically, I'm pulling out all the tricks. Should end up being cheaper than building my own vehicle from scratch and I'll have heat, windshield wipers, and 2 seats.
Not sure if this thing will be registered as a motorcycle or a car yet, but what they don't know won't hurt them
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Currently driving a mostly stock 2014 Mitsubishi Mirage DE hatchback.
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03-25-2013, 03:53 PM
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#25 (permalink)
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EcoModding Smurfer
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Aha, I forgot about the Metro. Perhaps design a tube chassis that incorporates the Metro mechanicals? The only things 'valuable' about the Metro is the light curb weight and fuel-sipping motor. Aero-wise, it leaves a lot to be desired.
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03-25-2013, 04:12 PM
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#26 (permalink)
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OCD Master EcoModder
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Yes the Metro is not very aero.
When you said "full streamlining" does that include a boat tail? That plus a belly pan and grill block should get you a very low Cd.
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Driving '00 Honda Insight, acquired Feb 2016.
Last edited by brucepick; 03-25-2013 at 04:19 PM..
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03-25-2013, 05:08 PM
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#27 (permalink)
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Master EcoModder
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I basically taking the "cab" portion off of the metro and building a new frame around it. Basically only using it for the doors, the windows, and the already designed drive train. It'll be nice to have a car with windshield wipers and stuff.
The only thing that is aerodynamically undesirable is the high pressure zone at the base of the windshield and the overall shape of the windshield. Unfortunately, there isn't much I can do about that.
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03-25-2013, 06:10 PM
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#28 (permalink)
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I would suggest lowering the top for two reasons. 1, reducing the frontal area will go a long way to reducing your CDA. 2, the lower the height of the car, the shorter your boat tail needs to be, the easier it is to make a larger percentage of a "complete" 100% boat tail "fit" onto your car.
Lengthening the wheel base is essential for a better boat tail. For my car a 80% boat tail would add between 6.5 and 7 feet. Then i have to deal with issues of ground clearance for hills etc. I f i could move the rear wheels back i wouldn't have that problem.
Look into Dave Clouds "Dolphin" for what he did to a second gen Metro if you haven't already.
http://ecomodder.com/forum/showthrea...hin-13142.html
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Last edited by sheepdog 44; 03-25-2013 at 06:16 PM..
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03-26-2013, 12:04 AM
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#29 (permalink)
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OCD Master EcoModder
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I think Sheepdog is getting at a concern related to mine. If u read a good bit in the aerodynamics sub-forum you will learn that the back end of the car is where serious losses are.
You can clean up the underbody with a belly pan, it doesn't require welding or fiberglass just care and patience. Grill block helps in several ways and is pretty easy unless you require a super-bling look.
However the car's back end sucks a huge vacuum behind it. You create the vacuum using energy created by the engine (= fuel used). The only real solutions we've found are to taper the rear, either a boat tail or a Kamm back which is really a chopped off boat tail. Untreated, it's a major source of drag.
A boat tail doesn't require a chopped top. Chopping would mean less length needed to taper it down to a given size. But chopping also means you're on your own for all the glass, probably won't have wipers, etc.
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Driving '00 Honda Insight, acquired Feb 2016.
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03-26-2013, 09:27 AM
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#30 (permalink)
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Master EcoModder
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There is a really important difference between a narrowed rear wheel track - and a single rear wheel. A single rear wheel will be unstable in all likelihood as you've drawn it - the tail should be a fish tail if you have one wheel so that there is no weight outside the triangle formed by the contact patches.
The Dolphin has much more side taper (which is good) and the wheelbase is extended, as well as keeping four wheels, all making it stable.
Take a look at the Aptera - the front wheels are SEVEN FEET apart and when the battery is kept near the front wheels, it was stable, but as weight crept toward the back (and got much heavier) it required extraordinary effort to keep it stable.
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