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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 11-19-2011, 07:27 PM   #11 (permalink)
Master EcoModder
 
kach22i's Avatar
 
Join Date: Jul 2011
Location: Ann Arbor, Michigan
Posts: 4,158
Thanks: 120
Thanked 2,790 Times in 1,959 Posts
Quote:
Originally Posted by rainagain View Post
Lawn edging, what a great idea!
It is, I've used the larger stuff on my truck. Link in signature below.

__________________
George
Architect, Artist and Designer of Objects

1977 Porsche 911s Targa
1998 Chevy S-10 Pick-Up truck
1989 Scat II HP Hovercraft

Chin Spoiler:
http://forums.pelicanparts.com/off-t...effective.html

Rear Spoiler Pick Up Truck
http://forums.pelicanparts.com/off-t...xperiment.html

Roof Wing
http://ecomodder.com/forum/showthrea...1-a-19525.html
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 11-20-2011, 01:30 AM   #12 (permalink)
Cd
Ultimate Fail
 
Cd's Avatar
 
Join Date: Feb 2008
Location: Austin,Texas
Posts: 3,585
Thanks: 2,872
Thanked 1,121 Times in 679 Posts
Sometimes tire spats that seem as though they would help the Cd count, really don't do much of anything.

When these spats were tested on this '80 Camaro, they didn't do anything for the Cd despite shielding those wheels sticking out into the wind.



Car Aerodynamics - A2 Wind Tunnel - Wind Camp Tech Theory
Here, Eaker is examining the stock Z28-type side spats, which did not alter the Cd but added 40 pounds of rear downforce. He thought they may be more helpful in yaw but says testing 0 degrees to the airflow gives you 75 percent of the data you'd need at slight yaw. We also tested the Moon discs, which reduced drag by two to four counts. The farther the wheels are from the outer edge of the fender, the less the discs matter. View Related Article


Read more: Chevy Camaro Aerodynamics Side Spats Photo 8

Aerodynamics can be puzzling sometimes. Truly unpredictable !
  Reply With Quote
The Following 2 Users Say Thank You to Cd For This Useful Post:
aerohead (10-18-2014), California98Civic (11-20-2011)
Old 11-20-2011, 03:35 PM   #13 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,299

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 2,373
Thanked 2,172 Times in 1,469 Posts
Quote:
Originally Posted by Cd View Post
Sometimes tire spats that seem as though they would help the Cd count, really don't do much of anything.
Very useful article. Thanks. Odd that they don't note a kamm back as a certain aero benefit in their list. The article PaleMelanesian posted has some interesting info on the placing and shaping of the spats, which apparently can make a lot of difference: Autospeed Modifying Under-Car Airflow. Maybe these spats on the camaro might have been shaped differently and had better effects?

Quote:
Originally Posted by Peter7307 View Post
California98Civic,
Nice job on the mods.
I would easily take them as being factory if you had not pointed out the changes you had made.

Peter.
Thanks Peter. I'm going to need to rebuild them when I lower the car soon.
__________________
See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.



  Reply With Quote
The Following User Says Thank You to California98Civic For This Useful Post:
aerohead (10-18-2014)
Old 11-20-2011, 06:38 PM   #14 (permalink)
Cd
Ultimate Fail
 
Cd's Avatar
 
Join Date: Feb 2008
Location: Austin,Texas
Posts: 3,585
Thanks: 2,872
Thanked 1,121 Times in 679 Posts
Quote:
Originally Posted by California98Civic View Post
Very useful article. Thanks. Odd that they don't note a kamm back as a certain aero benefit in their list. The article PaleMelanesian posted has some interesting info on the placing and shaping of the spats, which apparently can make a lot of difference: Autospeed Modifying Under-Car Airflow. Maybe these spats on the camaro might have been shaped differently and had better effects?
Spats certainly do make a difference. I was just showing the unpredictability of aero mods. Personally, I would have bet money ( and lost money ) by looking at the spats on that Camaro.
The area of the wheel sticking out in the wind is enormous ! I would have thought the spats would have dropped the Cd quite a bit.

While we are on the subject of that car, just look at the huge gaping wheel wells around that back tire ! No wheel skirts, yet a .201 !
And stock door handles and misaligned window trim as well !
That car LOOKS like an aero nightmare.
  Reply With Quote
The Following User Says Thank You to Cd For This Useful Post:
aerohead (10-18-2014)
Old 11-20-2011, 06:56 PM   #15 (permalink)
(:
 
Frank Lee's Avatar
 
Join Date: Jan 2008
Location: up north
Posts: 12,762

Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

Moon Unit - '98 Mercury Sable LX Wagon
90 day: 21.24 mpg (US)
Thanks: 1,585
Thanked 3,555 Times in 2,218 Posts
Like that boxy yet sleek old Lexus sedan, whatever that was.
__________________


  Reply With Quote
Old 11-21-2011, 06:46 PM   #16 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 15,861
Thanks: 23,922
Thanked 7,207 Times in 4,640 Posts
spat

Quote:
Originally Posted by Cd View Post
Sometimes tire spats that seem as though they would help the Cd count, really don't do much of anything.

When these spats were tested on this '80 Camaro, they didn't do anything for the Cd despite shielding those wheels sticking out into the wind.



Car Aerodynamics - A2 Wind Tunnel - Wind Camp Tech Theory
Here, Eaker is examining the stock Z28-type side spats, which did not alter the Cd but added 40 pounds of rear downforce. He thought they may be more helpful in yaw but says testing 0 degrees to the airflow gives you 75 percent of the data you'd need at slight yaw. We also tested the Moon discs, which reduced drag by two to four counts. The farther the wheels are from the outer edge of the fender, the less the discs matter. View Related Article


Read more: Chevy Camaro Aerodynamics Side Spats Photo 8

Aerodynamics can be puzzling sometimes. Truly unpredictable !
Without a wrap-around front airdam as wide as the width of the spat,the approaching air would be colliding with the tire face,spoiling an opportunity for the spat to function.
The Trans Am Firebird used 'leading' streamlining to clean up the flow for this region of the body.
  Reply With Quote
Old 11-21-2011, 07:23 PM   #17 (permalink)
tru
EcoModding Apprentice
 
Join Date: Aug 2011
Location: FL
Posts: 126

tru - '05 Ford Focus ZX3
90 day: 39.46 mpg (US)

the truck - '02 GMC Sierra Denali
Thanks: 0
Thanked 7 Times in 6 Posts
Quote:
Originally Posted by aerohead View Post
Without a wrap-around front airdam as wide as the width of the spat,the approaching air would be colliding with the tire face,spoiling an opportunity for the spat to function.
The Trans Am Firebird used 'leading' streamlining to clean up the flow for this region of the body.
I think ur confused, as was i on first inspection. the spat is on the front side upstream on the rear tires.
__________________
  Reply With Quote
Old 11-22-2011, 10:52 AM   #18 (permalink)
EcoModding Apprentice
 
Join Date: Nov 2011
Location: Middle TN
Posts: 111

WorkHorse - '88 Ford F150 XL
90 day: 13.5 mpg (US)

DailyBeater - '93 Ford Escort LX
Team Ford
90 day: 39.37 mpg (US)

The ST - '13 Ford Focus ST
90 day: 26.78 mpg (US)
Thanks: 0
Thanked 3 Times in 2 Posts
I took a crack at some innitial planning and designing last night at a buddies shop. We did a ton of thinking, messed with a few different materials he had layin around and eventually got to work on puttin together a simple "prototype to test out made of aluminum. I didnt want to go too low with the stuff and scrape it all the time so I went 3" below the stock bumper which is enough to cover all the "nastiness" as we call it thats previously left hangin in the wind LOL. We didnt have enough time to finish but the design looks alot like a stock chevy chin spoiler that is only in the front and doesnt wrap around. Im not sure I like it very much but might test it out when we finish and see what happens. Im thinkin I might grab some of that lawn edging and do one more like I wanted, where it wraps all the way around the bumper like the lower chin on the boxy Jettas and Golfs. We messed around with tire spat ideas as well, real simple like the old Prius used to have but will finish the spoiler first. No pics yet, but when I get the bracket together Ill post some up and get yall to critique it!
Matt
__________________
  Reply With Quote
Old 11-22-2011, 04:23 PM   #19 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 15,861
Thanks: 23,922
Thanked 7,207 Times in 4,640 Posts
rear

Quote:
Originally Posted by tru View Post
I think ur confused, as was i on first inspection. the spat is on the front side upstream on the rear tires.
I guess my reaction would be similar.Aft-body mods cannot function if the air to them is turbulent.
In the absence of an airdam and rocker panel extensions flush with the outside edge of the tires,the flow to the rear spat could be real 'trash',negating its effect.
  Reply With Quote
Old 11-23-2011, 02:50 PM   #20 (permalink)
Cd
Ultimate Fail
 
Cd's Avatar
 
Join Date: Feb 2008
Location: Austin,Texas
Posts: 3,585
Thanks: 2,872
Thanked 1,121 Times in 679 Posts
Quote:
Originally Posted by aerohead View Post
Without a wrap-around front airdam as wide as the width of the spat,the approaching air would be colliding with the tire face,spoiling an opportunity for the spat to function.
The Trans Am Firebird used 'leading' streamlining to clean up the flow for this region of the body.
I'm puzzled because the smooth wheels helped the drag yet the spat did nothing for the drag.

It sounds as if you mean that the front airdam keeps air from colliding with the tire, spoiling an opportunity for the spat to function, yet the wheel covers ( Moon discs ) functioned as they did, so plenty of air was getting to that area.

  Reply With Quote
Reply  Post New Thread


Thread Tools




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