Quote:
Inspection of the interior of the sectioned Inset devices, showed that fuel as it flows
through the device comes in contact with only the inner surface of central tube, the surfaces
of the twisted plate within the central tube, and the inner surfaces of the nipples at each end of
the device. Since the process of passing fuel through the Inset device entails nothing more
than flowing the fuel through a piece of pipe, there is no technical basis to support a claim
that the device modifies the fuel, and as a result causes an optimum burn of the fuel. The
conclusion drawn from inspection of the interior of the Inset device is that it can not have any
effect on either emissions or fuel economy.
From one of the links above. Too funny.