Briggs and Stratton 104M02-0083-F1 7.25 Gross Torque EXI Series7.25 Gross Torque EXI Series. This genuine 163cc Briggs & Stratton engine offers dependable power without sacrificing ease of use and user comfort. Advanced engineering delivers a lighter, quieter and smoother operating experience, and the ReadyStart no-prime starting system translates into fast, easy starts. ReadyStart® starting.