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Discussion Starter #1
This is for an electrically converted n/a.
I get great range when going surface street but the range drops significantly when I'm on the highway.

What have you done, aero wise, that has got you more mpg.

Things I haven't yet done
Get the front tires out of the airstream with an airdam closing off the mouth almost entirely- no radiator.

Full lexan under tray to stream line the undercarriage.

Some type of lexan deflector on the hood to get laminar airflow to stick to the hardtop and to get the windshield wipers out of the airstream.

Put some type of partial covers over the tops of the rear wheel arches.

Any suggestions or reasons why not to do the above would be appreciated.
 

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I have no idea & have nothing to contribute, other than maybe the tricks hypermilers do? Maybe lightweight wheels with narrow tread? figure a way to decrease panel gaps? I dunno... Interested to see pics of your car though... sounds interesting...
 

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Murse Magnet
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If I were doing this type of project my go to's would be the same as those on the forums for the honda insight. (insightcentral?)
They run a special tire that is ultra low rolling resistance that is then overinflated to about 50 psi.

I would run wheels like the insight that don't get air trapped into the wheel well. (Now that I think of it, I wonder if insight wheels have the same bolt pattern.

I would remove the side mirrors and install some small cameras with a screen on the inside in place of them.

I would close off the front grill all together.

Full under body like you mentioned should help but I don't know enough about aerodynamics for that.

I would see about lowering the car to the ground a bit more than stock ride height is.

I would make rear wheel fender covers to close off the rear wheels from getting any air flow.
 

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I hypermiled a 97mirage coupe.

you want thin aluminum wheels.
and tall tall thin tires.
remove the side mirrors.
lower the car.
you will want a lip. the garage door universal one is fine.
get CORAPLAST and make a full under body tray.
rebuild and relube your wheel bearings.
remove ps or both wiper blades.
clear silicone the gaps around the turn signals.
close in the grill.
rear bumper cut. gotta get the air out.
garage door molding side skirts.
look into a way to tear drop the rear.
change gear ratio in the rear. for lower RPM on highway.
look into creating lift. or reducing down force.

lots of fun.. i got 80MPG in that mirage.
 

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From the other thread:
This is for greesemonkey

What about that rear diffuser!

I converted an n/a to electric power and need every aero advantage I can find.

Did your mpg increase with that mod?

I think I need to start new topic
It was a Warhorse rear diffuser that the outer portions were removed after one side was damaged. I cannot say that I saw a increase in MPG's although I tracked gas mileage every tank with the aCar/Fuelly app and unfortunately no longer have that data to look at.

It was mounted to the chassis and while I'm sure it helped direct airflow, how affective it was I cannot say. Although that design was tested and shown to be effective.

It sounds like you are on the right track but definitely don't think lexan would the best choice for a flat bottom, alumalite would be the most cost effective option.
 

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Discussion Starter #6
Awesome for the reply greasemonkey, love the look of your car!

alumalite ain't cheap. Lexan isn't either but is really good against being hammered.

Our cars roll like crazy. Changing rims and tires to skinny don't go with the miata, besides the electric smokes the daisies in three gears with 205s already.

I don't like the video mirrors in they don't have depth perception. Someone should get the nintendo 3ds screen to work. Game changer.

The pressure flow shows low pressure off the top of the windshield and never really comes back to the car leaving the car in a turbulent mess. I no longer have a hot tailpipe and more cubic inches to differ more air to the rear of the car.

I'm not removing safety equipment.Gear ratio in an electric doesn't really matter.

Wheel well air is an issue. Spats or partial spats in the back will help, but not with the looks! Other than cutting fenders like I have seen, has anybody got any ideas.

It's an easy way to test with an electric - Freeway and a amp meter
 

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You don't want a traditional diffusor as they create downforce which increases rolling resistance.

205 wide tires are definitely too wide to be efficient. Try 165 and you'll see less energy consumption.

I'd also like to see a picture of your car as hypermiler cars usually tend to accept mileage over looks. covering the wheel wells is something you need to do if you want serious results. One alternative would be very flat rims (with the aforementioned skinny tires) that are flush with the fenders. My guess would be that covers would look better ;)
 

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Awesome for the reply greasemonkey, love the look of your car!

alumalite ain't cheap. Lexan isn't either but is really good against being hammered.

Our cars roll like crazy. Changing rims and tires to skinny don't go with the miata, besides the electric smokes the daisies in three gears with 205s already.

I don't like the video mirrors in they don't have depth perception. Someone should get the nintendo 3ds screen to work. Game changer.

The pressure flow shows low pressure off the top of the windshield and never really comes back to the car leaving the car in a turbulent mess. I no longer have a hot tailpipe and more cubic inches to differ more air to the rear of the car.

I'm not removing safety equipment.Gear ratio in an electric doesn't really matter.

Wheel well air is an issue. Spats or partial spats in the back will help, but not with the looks! Other than cutting fenders like I have seen, has anybody got any ideas.

It's an easy way to test with an electric - Freeway and a amp meter
Sounds like you don't want any of the simpler things that will help your issue. That usually leads down an expensive path...maybe... Tesla swap Miata?<---don't mind me, just being a bad influence here :)
 

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1000% Jake
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I would be building a flat floor with marine ply. I wish I could run one, but legally I can only go back to the front axle, so that's where my flat section stops. If you can clean that up completely you would see a pretty substantial benefit.



Just seal it and paint it. Lighter and cheaper than any other option.
 
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