[Derf00]

I know there have been a few posts about the Tornado Fuel Saver and a few other devices that claim increased MPG and HP for just a few bucks. Popular Science Sept' 05 issue has put some of the more popular and expensive ones to the test and provided their results. The tests were done using a 5.4L F350 Pickup. The summary is below:

Fuel OptiMiser $22: JCWhitney Catalog
Claims: magnetically rearranges fuel molecules making fuel burn more effeciently
Result: No impact on the dyno or MPG

Intake Twister $20: E-bay item
Claims: causes the fuel to 'spread out'. Increasing MPG 5-10mpg and HP by 10%
Result: Actually reduced MPG AND HP by 10%. Could also harm engine if it gets sucked in.

TornadoFuelSaver $70: Tons of posts on here about it
Claims: Creates a tornado effect in intake that is supposed to create a better mix increases MPG by 28% and HP by 4-13.
Result: Actually reduced MPG AND HP by 10%.

Electronic Engine Ionizer Fuel Saver $80:
Claims: Increase gas mileage by 30% electrochemically
Results: Actually reduced HP by about 10% and caught on fire!

Fuel Atomizer 2000 $200:
Claims: Increase of MPG by 300% (not a typo) and increase engine performance and HP
Results: No Impact on either HP or MPG

Aquatune $300:
Claims: Increase of 25% in MPG and 30% in HP
Results: 20% LOWER MPG and a loss of 20 peak HP