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The passenger car automakers are always competing to excel in vehicle characteristics related to passenger comfort and driveability aspects. The engine calibration is a theoretical and experimental procedure with the intention to extract maximum efficiency from the engine and guarantee satisfactory levels of driving for both conventional and racing cars. This paper describes the calibration procedure of a Formula SAE race car engine. The engine was a four cylinder 600 cm3 four-strokes with modified intake and exhaust systems, controlled by an engine control unit (Motec M800 ECU). These engines present optimized characteristics for high speed, in exchange for some combustion degradation in some specific operating conditions at low speed that may impair vehicle driveability. Therefore, good tip-in reaction and the progression of the torque delivery are fundamental criteria to increase the vehicle performance, specially, to those submitted to short acceleration distances.

In many vehicle motorsport categories, the one of the most important factors that lead a team to the victory is the suspension setup. Parameters like roll stiffness and camber changing are essential to the vehicle behavior during a driving situation. To handle these variables, features like suspension hardpoints arrangement, pivot points position and spring stiffness can be settled. However a setup only will perform a desirable effect if the chosen configuration does not change. Ideally, to make it possible, every component that holds suspension loads (suspension members, mounting plates and chassis) would have to be infinitely rigid. Even though it is not achievable, the existing deformation can be small enough to be negligible when compared with suspension displacement. In order to reach this target, this paper introduce a spring modeling and a Finite Element multibody modeling process of a Formula SAE prototype’s suspension and chassis.

Several motorsport competitions impose restrictions on intake systems to limit maximum engine power. Since the restriction interferes with the efficiency of the intake system as a whole, it is necessary to study ways to minimize the negative effect of changes in engine performance. In practice, the regulation imposes restrictions to the inlet air which motivates the search for the minimum pressure loss in the restrictor while maintaining an equal volumetric efficiency between the cylinders. This way, it is necessary to tune the duct lengths and diameters, and plenum volume to obtain the maximum volumetric efficiency in the most required speeds. Formula SAE competition imposes an intake system restriction of 20 mm or 19 mm diameter (for gasoline or ethanol fueled engines, respectively). Thus, to reduce pressure loss in the imposed restriction orifice, a system with a convergent divergent duct forming a venturi tube was used.