Metro aerodynamics - Page 21 - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Reply
 
Thread Tools Display Modes
 
Old 10-26-2006, 05:50 PM   #201
Registered Member
 
MetroMPG's Avatar
 
Join Date: Dec 2005
Posts: 4,223
Country: United States
I had the car rust-treated today, so I removed the rear wheel skirts.
__________________

MetroMPG is offline   Reply With Quote
Old 12-01-2006, 12:51 PM   #202
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,442
Country: United States
Send a message via Yahoo to JanGeo
Hey I just read a post in ScionLife that the drag coefficient of my xB is 0.35
__________________

JanGeo is offline   Reply With Quote
Old 12-13-2006, 01:48 PM   #203
Registered Member
 
Peakster's Avatar
 
Join Date: Sep 2006
Posts: 467
Country: United States
Lightbulb Dirt accumulation a good indication of poor aerodynamics?

It's been really gross and mucky outside, so washing my Metro would be dumb since it would just get dirty 10 minutes later. Now that my Metro is caked with road grime this is what she looks like:

Attachment 82

I would think that the clean parts of the car are where the air is going smoothly over the vehicle, but look at all that turbulent air coming from the front wheel arch! Also note how much dirt accumulation occurs on the rear of the car:

Attachment 83

Winter should be a perfect time to test out some Aero mods!
Attached Thumbnails
Click image for larger version

Name:	IM001172.JPG
Views:	279
Size:	64.8 KB
ID:	71   Click image for larger version

Name:	IM001173.JPG
Views:	268
Size:	75.8 KB
ID:	72  
Peakster is offline   Reply With Quote
Old 12-13-2006, 03:07 PM   #204
Registered Member
 
MetroMPG's Avatar
 
Join Date: Dec 2005
Posts: 4,223
Country: United States
I read somewhere that some aerodynamicists sometimes use dust in the wind tunnel for exactly the same reason - where it accumulates on the car shows areas of low pressure better.
MetroMPG is offline   Reply With Quote
Old 12-13-2006, 03:09 PM   #205
Registered Member
 
MetroMPG's Avatar
 
Join Date: Dec 2005
Posts: 4,223
Country: United States
Also, don't kick off the "snuds" (snow & mud) that accumulate behind your tires. Once they're built up, they effectively "boat tail" the air flowing past the wheels and help streamline it.
MetroMPG is offline   Reply With Quote
Old 12-13-2006, 04:52 PM   #206
Tuggin at the surly bonds
 
Silveredwings's Avatar
 
Join Date: Apr 2006
Posts: 839
Country: United States
Quote:
Originally Posted by MetroMPG
Also, don't kick off the "snuds" (snow & mud) that accumulate behind your tires. Once they're built up, they effectively "boat tail" the air flowing past the wheels and help streamline it.
Oh, I thought those were boogers.
__________________
Reality is merely an illusion, albeit a very persistent one. - Albert Einstein
Silveredwings is offline   Reply With Quote
Old 12-16-2006, 01:59 PM   #207
Registered Member
 
The Toecutter's Avatar
 
Join Date: Mar 2006
Posts: 612
Country: United States
Send a message via AIM to The Toecutter
Quote:
Hey I just read a post in ScionLife that the drag coefficient of my xB is 0.35
If I would have known that you were unaware of this number, I'd have told you!

I found that figure after seeing the AC Propulsion Ebox, wanting to see whether their claims for range and efficiency appeared reasonable, and then doing a search and plugging the numbers into the drag equations we all know about.
The Toecutter is offline   Reply With Quote
Old 12-22-2006, 07:39 PM   #208
Registered Member
 
Peakster's Avatar
 
Join Date: Sep 2006
Posts: 467
Country: United States
Thinking of doing some aero modifications at some point with my Geo. (even if it's just a one-time thing). Just a few images to bounce around on this site:
Attachment 112
What the air is probably currently doing:
Attachment 113
Attachment 109
Attachment 111
And of course if I was really ambitious:
Attachment 116
Should the rear end taper be the same height as the front point to leave the air least-disturbed when leaving the car?
Attached Thumbnails
Click image for larger version

Name:	Aero Geo #5.JPG
Views:	237
Size:	18.2 KB
ID:	98  
Attached Images
       
Peakster is offline   Reply With Quote
Old 12-22-2006, 10:37 PM   #209
Senior Member
 
CoyoteX's Avatar
 
Join Date: Dec 2012
Posts: 230
Country: United States
Location: Southern WV
Find a 93 flat bumper. I tested them and they are better. I don't have any real mileage numbers but from doing a pretty thorough coasting test I can say they are better for the front end than the curved bumper.

CoyoteX is offline   Reply With Quote
Old 12-22-2006, 11:03 PM   #210
Registered Member
 
Peakster's Avatar
 
Join Date: Sep 2006
Posts: 467
Country: United States
Quote:
Originally Posted by Coyote X
Find a 93 flat bumper. I tested them and they are better. I don't have any real mileage numbers but from doing a pretty thorough coasting test I can say they are better for the front end than the curved bumper.
I would've thought that a flatter front bumper would be better. The downward angle of my current bumper seems like it rams a lot of air under the car. This is also why my '85 Fiero had a Cd of 0.37 compared to the SE version having a Cd of 0.35:

Non aero nose (my '85 SC Fiero) Cd: 0.37:
Attachment 114
Aero nose ('86 SE Fiero) Cd: 0.35:
Attachment 115

It seems as a rule of thumb that air should flow around the sides or top of the car, not under it. The only problem is that I'm sure the '93 bumpers are not interchangeable with my '97. I would have to fabricate the flat bumper myself.
Attached Images
   
__________________

Peakster is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Is your vehicle set correctly? DTMAce General Fuel Topics 1 03-17-2010 06:21 AM
fuel economy question Creamycaesar General Fuel Topics 19 02-08-2010 08:37 AM
p07 ECU $15 Matt Timion For Sale 4 08-27-2006 12:25 PM
I will be bike riding across Iowa kickflipjr People Powered 11 08-02-2006 04:22 PM
Some glue that won't melt when it gets hot? SVOboy General Maintenance and Repair 16 08-01-2006 08:15 AM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 10:34 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.