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The Formula SAE (FSAE) rules require mounting an impact attenuator (IA) to the front part of the formula car. The IA is necessary to take fully into account not only lighter weight of the parts but also cost effectiveness as the total cost and the workability of manufacturing have much value to win the FSAE. In this paper, three different IAs, 1) a space frame structure with steel pipes (SSF), 2) a monocoque structure with aluminum (AM) and 3) a monocoque structure with Carbon Fiber Reinforced Plastic (CFRPM), were manufactured and compared with respect to the weight and the cost effectiveness under FSAE rules. The FEM simulations for the AM were performed and the calculated results showed good agreements with the experimental ones. However, the AM could not absorb the impact energy experimentally. The CFRPM could absorb the required impact energy with lighter structure compared to other IAs. The weight was half of the experimental SSF and 1/5 of the calculated AM.

The turbocharged 4-stroke internal combustion engine was developed for FSAE, the annual collegiate racing competition. The dry sump lubricant system with the custom scavenge pump, KF-SC07, was designed. The crank axle height was 192mm, 76.5% of KF2004. Custom cam-shafts were designed making the torque fluctuation decreased less than 50% of KF2005. The compression ratio was changed. And the maximum boost pressure and the maximum torque gain were 25kPa (0.25 kgf/cm2) and 11%, respectively.

The ideal torque curve of automotive engines should be high and flat from low engine speed. To achieve this, we installed a variable nozzle turbine (VNT) turbocharger to a retail natural aspirated (NA) small gasoline engine. In the VNT turbocharger, variable vanes are set around the turbine wheel and form nozzles that changed the flow velocity of the exhaust gas. The vane position was controlled to adjust intake pressure at a target. As a result, the maximum torque improved by 27% and the engine speed at maximum torque was lowered by 1550rpm. A flat torque curve was achieved from 5450rpm to 8000rpm.