International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 04 | Apr 2021 www.irjet.net p-ISSN: 2395-0072 © 2021, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 4521 Design Methodology of a Custom Limited Slip Differential for an FSAE Vehicle Manan Jagtap 1 , Shubhadeep Roy 2 , Yash Bhosale 3 , Shailendra Dayane 4 1 UG Student, School of Mechanical Engineering, MIT World Peace University, Pune, Maharashtra, India. 2 UG Student, School of Mechanical Engineering, MIT World Peace University, Pune, Maharashtra, India. 3 UG Student, School of Mechanical Engineering, MIT World Peace University, Pune, Maharashtra, India. 4 Assistant Professor, School of Mechanical Engineering, MIT World Peace University, Pune, Maharashtra, India. ---------------------------------------------------------------------***---------------------------------------------------------------------- Abstract - The role of differentials in the current motorsports community is quite significant in terms of handling and drivability of the vehicle. Limited slip differentials are quite popular in the racing community today due to its dynamic advantages over other differentials. In India, the availability of limited slip differentials is quite limited for motorsports. The objective of the presented work is to develop an optimum methodology to design an efficient Custom Limited Slip Differential for a Formula Student Vehicle. Entire work was performed under the Formula Student rulebook restrictions and guidelines for an efficient system buildup accompanying optimum design. The paper enlists various steps adopted for the design of the custom differential including data acquisition. Key Words: Limited Slip Differential, Locked Differential, Open Differential, Methodology, Clutch Type LSD, Vehicle Dynamics. 1. INTRODUCTION When a vehicle initiates a turn, it's quite evident that both the rear wheels follow different arcs (the outer wheel follows a different arc as compared to the inner one), hence both the rear wheels have to cover different distances for a given time frame which implies that both the rear wheels need to rotate at different speeds. This is the scenario where differential comes into picture. Differential plays an immense role in the turning of your car. Let us consider that a rear wheel drive car is turning left, then logically the left wheel should rotate at a lower speed and the right wheel should rotate at a higher speed. The differential is designed in such a way that both the wheels on the axle can rotate at different speeds allowing the car to take a smoother turn. There are mainly 3 types of mechanical differentials: 1. Open Differential 2. Locked Differential 3. Limited Slip Differential 1.1 Open Differential Open differential is the oldest and most commonly used differential across all types of cars. The reason being its reliability, simplicity and cost effectiveness. The engine powers ring gear on differential casing which further transmits it to the wheels via a pair of side gears and set of spider gears. Despite its wide usage, open differential has some limitations. All the power coming from the engine is sent to the wheel having least traction. So if one wheel of a car is stuck in mud, then all the power is sent to the same wheel. This makes the vehicles having open differential very unsuitable for off-road and racing purposes. Fig - 1: Open Differential 1.2 Locked Differential A locked differential (Also referred to as spool), limits both the wheels to rotate at same speed irrespective of any scenario. Unlike an open differential, a locked differential has the potential to provide 100% of the input torque to the wheel with high traction when the other wheel with low traction starts slipping. The major problem with a locked differential is that the vehicle would experience a considerable amount of understeer (since both the wheels spin at same rotational speed) with high tire degradation. It is widely used in go carts and V8 supercars. Spool differentials were a popular choice in the racing community before the introduction of limited slip differentials.