A main shaft bearing compartment seal system is described herein. The modified ring groove geometry creates two distinct cavities or steps for a piston ring and a wave spring. This concept provides a separate groove cavity for the spring independent of the fool-proofing and clearance cavity. This modified ring groove geometry increases first face coverage and reduces exposure risk for eccentricity of wave spring to piston ring, to avoid potential disengagement and improve function and performance of the seal assembly and engine.