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

Reply  Post New Thread
Submit Tools LinkBack Thread Tools
Old 02-06-2008, 01:51 AM   #1 (permalink)
EcoModding Lurker
Join Date: Jan 2008
Posts: 59
Thanks: 0
Thanked 1 Time in 1 Post
see the drag (simple method for visualizing airflow patterns)

you can see the drag if you mix up lampblack with water. not too runny but too wet to dry fast. be ready to move. then paint about a inch or so dots on 1/2 the car. drive fast. the dots will follow the airstream and show smooth flow and turbulence. if your a cut and tape man you can see more or less were to fill in. i don't think it will matter on the street that much, because back in the day ,i was a kid reading about it, you could go to a beach speed week and see what yours could do on the harder sand with their clocks. after they got their fastest time some would cut and tape. from what i can remember the top would go up under 10 mph at about 130. and the cars back then were funny boxes. maybe someone who is doing it could go to the library and look up old car mags from the late 50's and early 60's. take a look at the lead sleds to. an idea to fix it on your car maybe, is to tape it and fill the back with spray foam. wax the car, so it will come out easily and glue it back with silicone glue. it will come off the car if you need to work on it, or sell the car. sand and bodo it to a smooth shape.. i don't think silicone will melt that kind of foam but you should try on a small patch first

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

Old 02-06-2008, 09:38 AM   #2 (permalink)
Daox's Avatar
Join Date: Dec 2007
Location: Germantown, WI
Posts: 11,175

CM400E - '81 Honda CM400E
90 day: 51.49 mpg (US)

Daox's Grey Prius - '04 Toyota Prius
Team Toyota
90 day: 49.53 mpg (US)

Daox's Insight - '00 Honda Insight
90 day: 64.33 mpg (US)

Swarthy - '14 Mitsubishi Mirage DE
90 day: 56.69 mpg (US)
Thanks: 2,475
Thanked 2,538 Times in 1,530 Posts
Using wool tufts is also a good way to test if you have turbulent airflow in certain areas. It sounds easier to clean up too.

See here
Current project: A better alternator delete
  Reply With Quote
Old 02-06-2008, 09:53 AM   #3 (permalink)
Batman Junior
MetroMPG's Avatar
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,275

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

MPGiata - '90 Mazda Miata
90 day: 52.07 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 61.98 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 58.72 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)
Thanks: 3,811
Thanked 6,693 Times in 3,469 Posts
I've read something along these lines as well DAN - except using dark food colouring in dish soap. (And the dish soap washes off in a nice lather when you're done the test. )

I suppose the most obvious benefit for doing "drip testing" is that you can do it by yourself and view the results when you've stopped, rather than taking a passenger along with a video camera (or an additional car, if you can't see the tufts in the area you're interested in studying).
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: Oops, I did it again! Bought another cheap, 3-cylinder Mirage. Mods in progress...
Ecodriving test: Manual vs. automatic transmission MPG showdown

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
The Following User Says Thank You to MetroMPG For This Useful Post:
Cd (07-11-2012)
Old 02-06-2008, 12:03 PM   #4 (permalink)
Join Date: Dec 2007
Location: Bay Area
Posts: 1,151

The Miata - '01 Mazda MX-5 Miata
Thanks: 0
Thanked 21 Times in 18 Posts
^^ I've seen oil used too

the only problem with water, oil, etc. is that it's surface tension interferes... This makes it good for looking at bulk flow - but not so much for sporadic flow interference. Keep in mind, there is no easy method in real world testing (other than tunnel and smoke) that won't interfere
Cars have not created a new problem. They merely made more urgent the necessity to solve existing ones.
  Reply With Quote
The Following User Says Thank You to trebuchet03 For This Useful Post:
Cd (07-11-2012)
Old 02-06-2008, 04:35 PM   #5 (permalink)
Frank Lee's Avatar
Join Date: Jan 2008
Location: up north
Posts: 12,761

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 3,548 Times in 2,215 Posts
One thing about cars from the '50s and '60s is that their aerodynamics were terrible- similar to today's SUVs and pickups, if not worse. There was more room for easy improvements.


  Reply With Quote
Reply  Post New Thread

Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Sources of Aerodynamic Drag in Automobiles and Possible Solutions SVOboy Aerodynamics 12 02-17-2010 03:09 PM

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com