View Single Post
Old 11-28-2007, 09:55 AM   This thread is in the EcoModder Project Library | #1 (permalink)
MetroMPG
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 21,235

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: 2,988
Thanked 5,875 Times in 3,045 Posts
Side mirror drag & effect on fuel economy - quantified

(Originally written August 11/06)

You often hear people talking about removing side mirrors to reduce drag. Is it effective or worthwhile? That's what this thread is about.

Still that thread seemed to run out of steam. I'd like this one to perhaps lead to more concrete numbers, maybe encourage an experiment or 2 to confirm...)
  • Both the Civic VX and Metro XFi eschewed outside passenger side mirrors. Cost savings could have easily been the reason on both cars (mirrors on both sides weren't as commonplace in the 80's and early 90's as they are now).
    .
  • Phil Knox ran his aero-modded CRX at Bonneville, and says removing his side mirrors made no measurable difference in his top speed (radar-measurement)
    Yahoo! Groups
Yet so many aero concept cars omit the mirrors. For example...



GM's PNGV concept car

Quote:
Instead of outside side mirrors, the car uses tiny cameras — a set-up similar to that seen on the Cadillac Evoq concept car unveiled at the 1999 North American International Auto Show. "We knew we couldn't afford the 30 counts of drag, so we went with camera mirrors," said George Claypole, Vehicle Integration Engineer for GM's Advanced Technology Vehicles. - Automotive Engineering International Online
So there we have mirror drag quantified: "30 counts of drag" - which if I'm not mistaken means Cd ".03". Seems overly large to me, but there it is.

Anyone have their Cd formula handy for their vehicle want to translate that to FE savings at various speeds?

__________________
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