Tell that to the 100 or so people driving a Focus with an Aerocharger on it, a lot of them pushing 10psi and 200whp. There's even one guy running 9psi non-intercooled and has it mounted right under the stock intake manifold and he gets full boost by 2400rpms, he says he regularly passes Corvettes on the road course in his Focus. And this guy tuned the car with a Pectel, single handedly, and is one of the smartest guys on the Focus Forums.
Granted it is such a weird little turbo that it's hard to grasp that it does work. It uses Variable Vane technology to give you a set boost and is electronically controlled to give you more boost, basically flip a switch for high and low boost settings. Though it is flow limited to a certain amount of boost and power. The Focus kit will only do 200whp max at 10 psi and if you try to boost it more it will over spin the turbo and destroy it.
There was even a twin turbo kit with the Aerocharger for the NSX. The beauty of the Aerocharger is because it has it's own internal oil supply it can be mounted virtually in any possition.
