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A mathematical model for tribological analysis of different automotive- valve-train configurations has been developed as a part of the FLARE (Friction and Lubrication Analysis of Reciprocating Engines) package. The model is based on an in-depth kinematic analysis and on a rigid-body dynamic analysis, including dynamic analysis of the valve spring. Lubricant film thickness, contact pressures, and frictional power loss are predicted. A mixed-lubrication model is used to determine the friction force at the cam-follower interface. In addition, lifter rotation is modeled to predict its effect on frictional power loss. Detailed results are presented for a pushrod valve train. Also, this paper compares frictional power loss for five different valve train types. They are: direct-acting overhead cam, pushrod, end-pivoted finger follower, center-pivoted finger follower, and cam-in-head. The valve trains are made equivalent by keeping the valve lift and the no-follow speed the same.