“The Effect of Aerodynamic Drag on Fuel Economy”
"For passenger cars this means that aerodynamics is responsible for a much higher proportion of the fuel used in the highway cycle than the city cycle: 50% for highway; versus 20% for city. This means that if you make a 10% reduction in aerodynamic drag your highway fuel economy will improve by approximately 5%, and your city fuel economy by approximately 2%."
This is copied from url:
The Effect of Aerodynamic Drag on Fuel Economy | ARC
The company that claims the above seems very serious, rigorous and knowledgeable:
"Auto Research Center is a specialized research facility, which sells time in its various test rigs (such as our wind tunnel and seven post rig) and provides design and consultancy services to government/military, commercial vehicle, automotive and racing clientele. ARC prides itself on remaining a competent tier one supplier to multiple OEMs throughout these industries. We also offer scale model development, vehicle aerodynamics and vehicle dynamics capabilities and expertise, computer aided engineering software, vehicle dynamics software and computer modeling programs for the purpose of trackside simulation. ARC is a worldwide company that is committed to developing innovative solutions in the ever-changing field of transportation."
With private clients and OEM intellectual property jealous safe keeping, this company and its personnel do not write scientific papers freely or low cost accessible. They may publish on SAE with permission from the client. Reading these articles is not for free.
Anyway, with such credentials claims, I thing the above general rule they publish on their web site is credible. They offer some white papers under the "media" site thumb that are well supported by a solid bibliography.
The site offers some history notes :
"ARC was opened in 1998, as the North American headquarters for Reynard Motorsports. Reynard Motorsports was based at Reynard Park, Brackley, England and at that time was the largest race car designer and manufacture in the world, producing cars for both open wheel and sportscar racing. In the USA, the primary effort was on open wheel in Indycar/CART."
Yes, I think these guys know what they are talking about.
__________________
Acel
See many mods in detail with results on
my modification thread for my 1999 Acura EL, similar to US Civic EX
Facts, please, give me the facts! Theoretical knowledge is verified by empirical knowledge! Check Einstein's General Relativity Theory E=MC^2! Every few years some new astrophysics observation and data prove some of Einstein's theory predictions more than a century old.