Spiral Max?
 

What do you guys think about this thing?

Take time to read the personal testimonies (link about halfway down on the right of pagein the blue area).

http://www.spiralmax.com/

There is also the Motavator

http://www.rpmoutlet.com/musv6helix.htm

I thought about buying one and my horsepower seemed to go up and I thought I got better mpg. It could have been my imagination. Not sure.

Those products have been asked about on here before, and the general concensus was that they would impede airflow more than help it. You can swirl the air in the intake all you want, the runners and passages on the head are going to straighten it out. The "motovator" might help atomize the fuel better on a carburated car though. I haven't used either one so these are just opinions.:)

The actual MotorVator web site

http://www.motorvation.tv/motorvatorlayout.htm

Their marketing is not nearly as good but the idea is pretty much the same. This one at least does not reduce the size of the intake. On the Spiralmax, it looks like if you put a couple of those in, the cross sectional area of the air flow would be reduced. Like putting a reducing orifice in your fuel line would make sense.

Ford and GM would die for improved fleet fuel efficiencies per the EPA regulations. I am sure they could have either of these mass produced for a song. I guess they just don't know about this. Maybe we should tell them before Toyota finds out or god forbid KIA or Suburu.