Desenvolvimento de um motor V8 de alta performance

Abstract

Motorsports contributed greatly for the improvement of internal combustion engines because they adopted the engine as their primary power unit. This work aims the development of a high performance V8 engine for experimental vehicles and motorsport championships, promoting the pleasure of driving a powerful car with a remarkable sound, referring to Ferrari vehicles. The aim of this work is to develop a high performance V8 engine from adaptations in four-cylinder engines available on the market, to be marketed in motorsport championships and among engine enthusiasts. For that, the first step was to select a suitable engine for the adaptation, considering factors such as availability and cost of the components, ease of adaptation to the V configuration, weight and power. After choosing which engine to use, reverse engineering of this engine was made, measuring main geometric aspects to initiate the adaptation to the V arrangement in CAD software. Besides, parameters such as valve lifts and discharge coefficients were measured to perform 1-D thermodynamic simulations to obtain performance curves. Additionally, dynamic simulations were performed to evaluate the forces acting on the engine main bearings due to inertia and combustion forces. The chosen engine was a sport bike one, by the fact that it is a light, powerful engine and it has parts that help the adaptation to the V arrangement. Reverse engineering of this engine was made and the necessary parameters to the adaptation and the simulations were obtained. Furthermore, the simulated engine performance curves were similar to commercial four-cylinder engines. Besides, with the implementation of the dynamic simulation, it was noted that in comparison with the model without counterweights, the one with the four-cylinder counterweights increased the unbalance of the engine, not fulfilling its primary purpose of balancing the engine. Taking back to the V8 engine adaptation, this process followed design decisions such as the use of a flat-plane crankshaft and a dry sump system. The result of this adaptation was an engine block of 625 mm of length, 570 mm of width, 445 mm of height and a mass of 85 kg. Thermodynamic simulation of this engine indicated a peak torque of 282,6 Nm at 8.000 rpm and a peak power of 259,8 kW at 9.500 rpm, resulting in a power-to-weight ratio of 4,09 hp/kg, comparing with V8 engines designed by companies specialized in adapting commercial engines to high performance.