jennrod12
Posts: 223
Joined: Sat Feb 11, 2012 8:51 pm
Location: Santa Clara, CA

Re: iMiEV CdA?

Mon May 07, 2012 12:35 pm

Hi Archie,

Can you post a picture of your Smart car with the Airtabs mounted? It sounds like something that might be good for those of us with a highway commute, as I notice that the i-MiEV really gets buffeted by the wind. Unfortunately, my anti-virus blocks that website, so I can't view the gallery.

Thanks,

Jenn
2012 Diamond White i-MiEV ES
with green racing stripes and hubcaps (thanks to WeeJohn)
Santa Clara, CA

dsmall24us
Posts: 21
Joined: Sat Mar 31, 2012 12:58 pm

Re: iMiEV CdA?

Mon May 07, 2012 1:07 pm

Archie

I wish I had known about these earlier. I am trading in my Smart for the i. After looking at the pictures I am a little confused about the location for attaching the air tabs. Some show on the roof and some are on both sides at the rear. Could you explain where they would go on the i.
Thanks

Dan

jray3
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Location: Tacoma area, WA
Contact: Website

Re: iMiEV CdA?

Mon May 07, 2012 5:46 pm

Oh Boy, AirTabs border on an article of faith. They've been discussed at length on EcoModders, and been classified as a "Unicorn" http://ecomodder.com/forum/showthread.p ... 209-3.html
However, if they don't improve range but do increase stability, I'm interested in giving 'em a whirl.
2012 i-SE "MR BEAN" 76,000 miles
i-ES traded at 21,648 miles
2000 Honda Odyssey
1987 F250 Diesel
1983 Grumman Kurbwatt,170 kW, 32 kWh
1983 Mazda RX-7 EV 43 kW 10 kWh
1971 "Karmann Eclectric" EV 240 kW 19 kWh
1965 Karmann Ghia Cabriolet

archie_b
Site Moderator
Posts: 126
Joined: Sun Dec 25, 2011 5:51 pm

Re: iMiEV CdA?

Mon May 07, 2012 10:31 pm

I mounted six Airtabs just on the roof of my Smart. I could have mounted four more, for a total of ten, but was satisfied with the results just using six. Also by only mounting in the center of the roof I minimized the visibility of the Airtabs. Being a black Smart with black Airtabs they didn't jump out when looking at the car like some of the other examples on the Airtab web site.

Did they provide more stability for the Smart at highway speeds? Absolutely. No more grab the wheel with both hands when a semi passes or is just in front of the car. No more darting from side to side in a crosswind. Did they make the Smart handle like a Corvette? No, but it did make it handle like a regular compact sedan. Big improvement. Airtabs have the biggest effect on flat ended vehicles, like semi trailers, vans, Smarts and the i.

As for increasing range, don't expect any big increases, but it will help. Expect somewhere in the 1-3% range. Don't expect any increase in range at speeds below 45-50 mph. The faster you drive, the more the effect. I've owned a first gen Insight for 12 years and that car is loaded with improvements that give .5% here, 1% there, 2% over there, etc. The end result was the first car rated at 70mpg highway. I live where it routinely gets below zero and snows a lot during the winter months which drastictly reduces gas mileage. I still have averaged 62.5mpg over 12 years of use.

Airtabs are inexpensive and are attached using adhesive. This means you can remove them easily if not satisfied with the results. Hopefully someone with an i that drives at highway speeds will give them a try and report back with the results.

dumemama
Posts: 28
Joined: Sat Mar 03, 2012 9:38 am
Location: Malibu Appalacians

Re: iMiEV CdA?

Sun May 13, 2012 10:43 pm

Archie,

Can you say whether the airtabs helped much with accumulation of dirt on the back of your smart? I live on a dirt road. The back of my subaru outback is always completely covered with a thick layer of fine dust from our road. I'm not looking forward to that on my sparkling white i. The dust storm is also rather rude to the neighbors hiking and horseback riding. I'd get the airtabs just for that.

Barb
-Barb
2012 White ES w/QC, 4/30/12

archie_b
Site Moderator
Posts: 126
Joined: Sun Dec 25, 2011 5:51 pm

Re: iMiEV CdA?

Mon May 14, 2012 9:31 am

Barb:

I don't think the Airtabs will reduce the dirt you kick up driving on the dirt road, both because of low speed and because the tires are what is mostly kicking up the dust. If once you get on a paved road you get up to speeds above 50 mph it could lessen the dirt that accumulated on the back, but it will not eliminate it. I still got dirt and road spray on the back of my Smart, just that the quantity was significantly less.

There is a product you may want to try which might help. The product is RejeX and here is the web site: http://www.rejex.com
I have used this product for about 6 years and it does what it says it will do. It can be used on glass also and this along with the Airtabs could keep the back end of your Subaru and the i cleaner. Hope this was helpful.

jennrod12
Posts: 223
Joined: Sat Feb 11, 2012 8:51 pm
Location: Santa Clara, CA

Re: iMiEV CdA?

Mon May 28, 2012 8:34 pm

If I get a new job that requires freeway commuting, I will definitely try them. It looks like I will need to mount them on the roof-proper, not on the top of the hatch, because they might not clear when opening the hatch. Archie, does that sound right to you? Also, do you think there would be any advantage to also mounting some on the sides at the back of the car?

Thanks,

Jenn
2012 Diamond White i-MiEV ES
with green racing stripes and hubcaps (thanks to WeeJohn)
Santa Clara, CA

JoeS
Site Moderator
Posts: 3258
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Location: Los Altos Hills, California

Re: iMiEV CdA?

Mon Jun 04, 2012 8:21 pm

With the background that Mitsubishi had with vortex generators on the Evo Lancer, one must wonder why Mitsu didn't incorporate them into the iMiEV.

http://www.mitsubishi-motors.com/corporate/about_us/technology/review/e/pdf/2004/16E_03.pdf

Anyway, this topic is pretty nicely picked-apart in this series of four articles ...

http://www.autospeed.com/A_3058/cms/article.html

http://www.autospeed.com/A_3059/cms/article.html

http://www.autospeed.com/A_3059/cms/article.html

http://autospeed.com/cms/title_Blowing-the-Vortex-Part-4/A_3061/article.html

When testing (unscientifically) on a Gen1 Honda Insight they saw a 5%-7% increase in fuel consumption. But, is there any relationship between this and the squared-off iMiEV aft end?

BTW, the new Toyota Prius C has tiny vortex generators molded into it taillight lens assembly. Interesting...

http://ecomodder.com/forum/showthread.php/factory-oem-vortex-generators-trailing-edge-side-toyota-20835.html

In any case, it still might be fun to try either these or other brands (anything physically smaller?) to see if they have any effect - like maybe just keeping the back of the car less dirty! :roll:
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

oahumiev
Posts: 57
Joined: Thu Jan 26, 2012 12:32 am
Location: Oahu, Hawaii

Re: iMiEV CdA?

Mon Jun 04, 2012 8:49 pm

jennrod12 wrote:It looks like I will need to mount them on the roof-proper, not on the top of the hatch, because they might not clear when opening the hatch. Archie, does that sound right to you?

Jenn


Jenn, I just purchased some of these off the web and will be mounting them in a few days hopefully. I am planning on mounting them on the roof proper before the gap between the roof and hatch, might actually help to make it more aerodynamic there as the gap is wide enough for some drag. Noticed in photos that in the UK the Miev's seem to have an extended hatch cover http://all-mitsubishi.info/wp-content/u ... _White.JPG
wonder why US version didn't get this?

jennrod12
Posts: 223
Joined: Sat Feb 11, 2012 8:51 pm
Location: Santa Clara, CA

Re: iMiEV CdA?

Tue Jun 05, 2012 9:05 am

Cool, let me know how it goes! How many did you get? Hopefully you can post a picture, too.

I think we didn't get the extended hatch cover because our car is wider. I'd really like that hatch cover. :(

Jenn
2012 Diamond White i-MiEV ES
with green racing stripes and hubcaps (thanks to WeeJohn)
Santa Clara, CA

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