Price of "mods" to improve fuel economy VS cost !

Here's another decent article with good testing methods:http://www.omninerd.com/articles/Improve_MPG_The_Factors_Affecting_Fuel_Efficiency

Summary:

 

^^

Wow, no mention of coasting to a stop? IMO and experience that and reducing top speed are tops on the list of ways to save gas. I watch people zoom up to red lights and stop signs then slam on the brakes all day long. It's particularly amusing when I can watch something like a Civic doing it, all the while thinking I'm actually getting better MPGs than they are (at least at that moment )

 

Can you really get better mileage from high octane fuel??? My experience has been that premium gas burns faster and doesn't seem to last as long.

 

Agreed with all of Evil Monkey's sayings (which are pretty logic and intelligent). I have hard time to believe that a change in air filter would lead to fuel economy, since you just close throttle more which lead to same restriction.

Only thing I could have thought is that it could lead to slightly more ignition advance, since ECU would sense a ''more closed'' throttle position while driving speed, but I hightly doubt that.