This is a new variable valve timing method which Chrysler has implemented in the new upcoming '08 Viper. The new design of the cam is such that it allows the lobe separation angle(LSA) to be changed on the fly. Note that the lobe separation angle is the angle between the exhaust and intake lobe centerlines, and is a defining factor for a cam's performance. A larger LSA would provide more low-end torque and a smaller LSA would provide better top-end torque.
The cam actually has another cam inside it. This inner cam can be used to control the intake lobes of the main cam, while the exhaust cams remain fixed.
This arrangement allows the ECU to change the LSA up to 40 degrees.
This was done to give the Viper's V10 more air to breathe at higher rpms, and because of it, the new Viper will be rated around 600hp...
