K&N Air Filter: Testing for MPG Change, Do they help? Hinder? I attempt to find out Options

[NevynPA]

So, FSUSpectra was kind enough to send me his K&N air filter that he wasn't using for me to test and shed some light on the big question:


Does a K&N air filter help you get better MPG?


There are two sides to this, and while my testing won't put the question to rest once and for all, it will at least provide some results that will hopefully be useful.

I've uploaded the videos I have so far to YouTube and created a playlist for them:

http://www.youtube.com/playlist?list=PL05C4F32D9B4E1CB0

I have still photos as well, and they will be hosted (elsewhere) and posted (here).



Plaintiff: K&N filters are bad for MPG.

Argument: K&N designed their air filters to be more free-flowing than the conventional air filter. By allowing more air into the engine, the ECU then adjusts the amount of fuel injected to compensate for the greater mass of air in order to maintain the proper air/fuel ratio. More fuel being injected means more fuel burned, thus lower MPG.

Defendant: K&N filters are good for MPG.

Argument: With the additional air being brought in by the engine, it develops more power. This added boost of power allows the engine to run more efficiently, increasing MPG. The extra power allows the engine to be able to work efficiently in higher gears (4th/5th) at a lower speed, thus delaying the need for a downshift to a less efficient gear.

Evidence: