Modifiedf 1: Compared with the original/standard cam, the lift is the same, but it is wider, so it can make the engine smoother at medium and high RPM and the torque greater, increase power.
Modifiedf 2: The lift is higher than the original and Modifiedf 1, which can improve the performance of the engine at high RPM, increase power, higher efficiency and lower noise. But at the same time, the power at low RPM will be weakened.