Cartridge KP39 54399880109 54397100508 Proton Exora

What is a ball bearing turbo?
Conventional turbos use oil filled floating journal bearings to allow the shaft to rotate, and thrust bearings to prevent the shaft from moving backwards and forwards in the turbo core (please see the diagram in the Turbo Basics section). Ball bearing turbos use a ball bearing pack in the turbo core to both allow rotation and prevent shaft movement. The advantage of this system is a marked reduction in rotational friction, producing lower lag.

What is a variable vane turbo?
Because turbos have to deal with a very wide variation in air flow through a fixed size and shaped housing with fixed shaped turbine blades this represents a compromise rather than optimal performance. A variable vane turbo uses a method to dynamically alter the shape of the exhaust housing depending on how much boost it is producing. This allows for a more efficient gas flow across the turbine and therefore lower lag. The shape of the housing is altered by using a concentric ring of blades in the exhaust which can be forced to fan out in the air stream. The second benefit of this setup is eliminate the need for a wastegate. Once the turbo reaches its maximum speed the change in the angle of the blades reduces the efficiency of the turbine, preventing it from spinning any faster.