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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 03-29-2008, 01:45 AM   #1 (permalink)
Master EcoModder
 
Join Date: Mar 2008
Location: USA
Posts: 560
Thanks: 1
Thanked 67 Times in 53 Posts
Coroplast undertray question (covering the control arms)

Since Coroplast seems to work well for undertray applications, and since it's flexible, why not make a chin undertray that is long enough to go from the bottom of the front bumper and attach to the aft edges of the control arms?

Most such undertrays end at the leading edge of the control arms, with cutouts to allow lock to lock steering travel of the wheels/tires.

However, given the flexibility of Coroplast, the inboard section of the control arms could be covered, to smoothen airflow as far aft as possible. As the contol arms move up and down with road contour, the Coroplast would flex, but have the smallest possible cutout for the wheels.

Why not?

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 03-29-2008, 09:39 AM   #2 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 21,252

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

MPGiata - '90 Mazda Miata
90 day: 52.8 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 73.57 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 55.99 mpg (US)
Thanks: 3,007
Thanked 5,891 Times in 3,053 Posts
No reason why not.

When I made the tray for my car, I effectively did that. Front and rear control arms were covered, with allowance for suspension travel.
__________________
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L



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 03-29-2008, 11:28 AM   #3 (permalink)
EcoModding Lurker
 
Join Date: Mar 2008
Location: Savannah
Posts: 23

2005 CivicEX - '05 Honda Civic EX
90 day: 37.26 mpg (US)
Thanks: 0
Thanked 0 Times in 0 Posts
Do alot of you cover the exhaust pipe when make a undertray? I would think it too hot for coroplast. What kinds of issues do you run into with having a undertray? A lot of questions 'cause I'm new to this type of modding. Thanks.
__________________
  Reply With Quote
Old 03-29-2008, 12:49 PM   #4 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 21,252

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

MPGiata - '90 Mazda Miata
90 day: 52.8 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 73.57 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 55.99 mpg (US)
Thanks: 3,007
Thanked 5,891 Times in 3,053 Posts
I used aluminum flashing rather than coroplast in the areas near the exhaust.

I didn't cover the catalytic converter though - I made a cutout around it.
__________________
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L



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 03-29-2009, 08:48 PM   #5 (permalink)
high school
 
ModelE's Avatar
 
Join Date: Oct 2008
Location: Boston, Ma.
Posts: 86

sabre - '02 Buick LeSabre Custom
90 day: 23.45 mpg (US)

frontier - '04 Nissan Frontier XE
90 day: 18.97 mpg (US)
Thanks: 0
Thanked 0 Times in 0 Posts
good call metro, covering the cat is a big no no. Can get a car lit on fire if your not careful. some truck fires on beaches start like that, guy digs in, covers cat, keeps trying to drive out, boom catches fire.
__________________
  Reply With Quote
Old 03-29-2009, 09:13 PM   #6 (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
Hm. You'd think the sand would leach heat from the cat, rather than insulate it.

Sheets of dense plastic work OK for under trays? It's either that or sheet metal from an old water heater, for me, since I'm not really into buying new stuff for eco-modding when there is so much usable stuff around me.
__________________
"ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"

  Reply With Quote
Old 03-30-2009, 10:06 AM   #7 (permalink)
Master EcoModder
 
vtec-e's Avatar
 
Join Date: May 2008
Location: Ireland
Posts: 507

De Yaris - '04 toyota yaris T2
90 day: 69.55 mpg (US)
Thanks: 111
Thanked 32 Times in 22 Posts
Quote:
Originally Posted by cerdmier View Post
What kinds of issues do you run into with having a undertray? A lot of questions 'cause I'm new to this type of modding. Thanks.
When i put an undertray under the back of my civic, i upset the airflow through the cabin as the exhaust vent is behind the rear bumper and must have required a negative pressure in that area to work. Installing the tray blocked off that area so i cut a little vent there and put in some flexi duct with no improvement. My windows fogged up constantly right up until i retired my civic. So i'll have to watch that when i undertray my yaris then......

ollie
  Reply With Quote
Old 03-30-2009, 12:08 PM   #8 (permalink)
EcoModding Apprentice
 
Bicycle Bob's Avatar
 
Join Date: May 2008
Location: N. Saskatchewan, CA
Posts: 1,521

Appliance White - '93 Geo Metro 4-Dr. Auto
Last 3: 42.35 mpg (US)

Stealth RV - '91 Chevy Sprint Base
Thanks: 72
Thanked 298 Times in 209 Posts
I'd rather let the suspension occasionally push the Coroplast down than cut holes in it. If the mounting points are close to a flex area, you can use a flat spring for some offset and flex between the car and the pan.
  Reply With Quote
Old 03-30-2009, 01:27 PM   #9 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 21,252

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

MPGiata - '90 Mazda Miata
90 day: 52.8 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 73.57 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 55.99 mpg (US)
Thanks: 3,007
Thanked 5,891 Times in 3,053 Posts
Coyote used stretchable rubber for the portion of the undertray over his rear control arms, if I'm not mistaken. Inner tube rubber, or the stuff used to line small ponds, I forget which.

__________________
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L



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
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Honda IACV explained TomO Off-Topic Tech 16 12-21-2015 02:49 AM
Coroplast question Otto Aerodynamics 14 03-28-2008 12:45 AM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com