Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 12-06-2009, 08:19 PM   #251 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,513

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.71 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 60.16 mpg (US)
Thanks: 4,058
Thanked 6,957 Times in 3,602 Posts
guitarguy: no, the fairing behind the wheel wasn't tested. (Meaning there's room for further gains )

Topher: You wouldn't be able to just add a Kammback + boat tail combo on a Metro and predict a ~20% improvement (Kammback was ~4.9 %)

All the other aero stuff I've done upstream affects the performance of the tail - meaning it wouldn't work as well without these:
  • partial grille block,
  • headlight gaps sealed
  • hood/bumper gap closed
  • pass mirror delete,
  • partial cowl block,
  • wipers were off
  • smooth wheel covers
  • rear fender skirts
  • and the big one: full smooth undertray
  • EDIT: forgot radio antenna delete

__________________
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
Ecodriving test: Manual vs. automatic transmission MPG showdown



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 12-06-2009, 08:20 PM   #252 (permalink)
Master EcoModder
 
Join Date: Nov 2008
Location: Madison AL
Posts: 1,123

The Geo - '93 Geo Metro
Team Metro
90 day: 45.16 mpg (US)
Thanks: 30
Thanked 40 Times in 37 Posts
Holy crap. You are talking INSANE numbers for a non leanburn engine. 75 mpg is now possible... take THAT GM.
  Reply With Quote
Old 12-06-2009, 08:27 PM   #253 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,513

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.71 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 60.16 mpg (US)
Thanks: 4,058
Thanked 6,957 Times in 3,602 Posts
GM and all the other automakers know that 75+ mpg is possible from a light, low drag vehicle with a conventional engine.

(EDIT: a vehicle they are convinced will not sell in large numbers - and they're probably right.)

Quote:
Dr. Paul MacCready predicted that a car,like the Impact (GM EV1, Cd 0.195) ,if produced as a gasoline-powered car,would achieve upwards of 100-mpg. -- aerohead
It's easy to find examples of streamlined concept /prototype cars with conventional drivetrains that get exceptional mileage.
__________________
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
Ecodriving test: Manual vs. automatic transmission MPG showdown



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
Old 12-06-2009, 08:31 PM   #254 (permalink)
Moderate your Moderation.
 
Join Date: Nov 2008
Location: Troy, Pa.
Posts: 8,919

Pasta - '96 Volkswagen Passat TDi
90 day: 45.22 mpg (US)
Thanks: 1,369
Thanked 430 Times in 353 Posts
concept/prototype... what about real world? Not so easy, eh?

Darin - yeah, the excitement led me astray..> I forgot your car was also altered in other ways. Still, a very nice gain.

Plan on testing those wheel tails any time soon?
__________________
"¿ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"

  Reply With Quote
Old 12-06-2009, 08:33 PM   #255 (permalink)
Master EcoModder
 
Join Date: Nov 2009
Location: Leadville, CO
Posts: 509

Maroon Ballon - '98 Chrysler Town & Country LXI
90 day: 26.42 mpg (US)

MaEsTRO - '95 Geo Metro 5spd hatch, 3 cyl
Thanks: 47
Thanked 54 Times in 38 Posts
As difficult as it would be to install/remove the undertray, I don't suppose you did A-B-A testing with that, but do you have any figures or a good guess as to how much the difference the undertray by itself would make?
  Reply With Quote
Old 12-06-2009, 08:45 PM   #256 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,513

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.71 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 60.16 mpg (US)
Thanks: 4,058
Thanked 6,957 Times in 3,602 Posts
I did A-B testing only on the undertray (because it was difficult to re-install, as you said).

It showed about a 2% improvement.

The numbers I have from the undertray + the boat tail suggest the combination of the two is greater than the sum of their individual effects taken separately.

Meaning: if I were to leave the boat tail on, and test just the undertray, we'd see greater than a 2% improvement from it (because the best maximum performance of the boat tail depends on the smooth flow provided by the undertray).
__________________
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
Ecodriving test: Manual vs. automatic transmission MPG showdown



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
Old 12-06-2009, 09:43 PM   #257 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,513

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.71 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 60.16 mpg (US)
Thanks: 4,058
Thanked 6,957 Times in 3,602 Posts
Quote:
Originally Posted by Christ View Post
concept/prototype... what about real world? Not so easy, eh?
Easy to build. Harder to sell, I suspect.

Quote:
Plan on testing those wheel tails any time soon?
Nope! Gotta save something for next summer.
__________________
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
Ecodriving test: Manual vs. automatic transmission MPG showdown



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
Old 12-06-2009, 09:47 PM   #258 (permalink)
Moderate your Moderation.
 
Join Date: Nov 2008
Location: Troy, Pa.
Posts: 8,919

Pasta - '96 Volkswagen Passat TDi
90 day: 45.22 mpg (US)
Thanks: 1,369
Thanked 430 Times in 353 Posts
Summer isn't too far off, my friend. Just think, Winter's coming soon, and then comes the Vernus (Spring), and then comes Summer. I'm sure you'll be working on something during the spring time, no?
__________________
"¿ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"

  Reply With Quote
Old 12-06-2009, 09:49 PM   #259 (permalink)
Grrr :-)
 
Nerys's Avatar
 
Join Date: May 2008
Location: Levittown PA
Posts: 800

Cherokee - '88 Jeep Cherokee
90 day: 19.44 mpg (US)

Ryo-Ohki - '94 Geo Metro Xfi
90 day: 50.15 mpg (US)

Vger 2 - '00 Plymouth Grand Voyager SE

Ninja - '89 Geo Tracker
90 day: 30.27 mpg (US)
Thanks: 12
Thanked 31 Times in 25 Posts
WOW. ok I think I am going to have to build one of these I am truly shocked it was THAT BIG and that big EVEN WITH the already in place Kamback improvements.

If your up for it (I KNOW its a ton of work) unless you already have the data?? ie what kind of improvement would JUST the tail make over a stock car? no belly no wheel skirts etc.. anyway to calculate that?

truly wow. Time to go find some coroplast!

I also wonder if I can test angles WITHOUT driving. IE big massive fan into a difuser array to straighten the airflow (think wright brothers wind tunnel)

I could aim the fan in the direction I want to test put a panel with tufts in place and adjust to see the changes in real time in the drive way.

do you think this would work?

Last edited by Nerys; 12-06-2009 at 09:57 PM..
  Reply With Quote
Old 12-06-2009, 10:10 PM   #260 (permalink)
A madman
 
brucey's Avatar
 
Join Date: Mar 2008
Location: WV
Posts: 1,018

Pequod - '17 Subaru Outback
90 day: 22.79 mpg (US)
Thanks: 73
Thanked 183 Times in 98 Posts
Send a message via AIM to brucey
I really want to re do my tail now after seeing a 15% increase in yours. Damn!

Mine showed up absolutely nothing. But it also was a lot steeper. I fail.

  Reply With Quote
Reply  Post New Thread


Tags
boat tail, testing

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Project: Rebuilding an '01 Honda Insight as a nonhybrid Fabio Hybrids 158 01-12-2013 11:59 AM
How to get instant fuel consumption from Megasquirt TELVM Instrumentation 11 08-29-2011 02:47 PM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com