Haptic skills are essential for effective Cardiopulmonary Resuscitation (CPR). Existing CPR training simulators provide unrealistic chest conditions. It is assumed that the CPR performance on a real human chest is the same even when the trainees have learnt on unrealistic dummy chests. To test this assumption we have developed an immersive Virtual Reality based CPR simulator in which force feedback is provided using a dummy chest with a linear spring mounted on a force plate. The user applied force is mapped to visual chest compressions modeling various springs, either linear or non-linear. Two groups of subjects were trained either with linear or non-linear chests. Both the groups were tested for their CPR performance on an unknown non-linear chest and their performance score was compared. The % of mean and standard deviation of the score (p value: 0.001) for the group with the non-linear chest is 91.66% and 1.70% and that with linear chest is 86.39% and 3.44% respectively. This suggests that the group that were trained on non-linear chest performed better. The experiments clearly demonstrates that visual feedback could influence haptics perception of chest compliance and the VR-CPR system could simulate various linear and non-linear chest compliance controlling visual feedback alone.