whats the stage 1 stage 2 and 3 for turbo?

Answer 1

its not an absolute scale. every manufacturer of turbo kits has their own grade. it basically is just which kit you get. they just call them stages because they usually build on eachother (a stage 2 kit is often a stage 1 kit with some extra or larger parts). A stage one kit from one manufacturer has no correlation to a stage one kit from another.