Do rear locking/limited slip diffs increase or decrease oversteer? What about on the front axle? What do they actually do to the driving dynamics?
>>28120443A car without a mechanical LSD is just a novelty car
>>28120443Its a mix bag.Locking left and right wheel to the same speed or limit to be closer is obviously creates understeer by thrust vectoring, Because during a turn, outside track is longer than inside, thus outside wheel should move faster than inside. By locking, it forces outside to roll slower, acting as braking on the outside, and forces inside wheel to roll faster, acting as inside gas, there for making the vehicle go straight.However other factors has to be considered.First is geometry, that most vehicle other than kart is longer than it is wide, this aspect ratio means the lateral(sideway) grip of the front and back wheels is usually more important than thrust difference on the left and right wheels thrust forward or backward. Adjusting the front or back anti-roll bar is thus the most effective factor in balance. Oversteering is caused by the front grips much better than the rear, thus tougher front anti-roll or softer rear would make stable as wheels more evenly loaded gets more grip overall.Second is this mechanism rely on the fact both wheel can provide equal grip given by equal normal force(downforce), but there are weight transfer on the front and back, as well as left and right. The amount of weight transfer depends on the center of mass, the height and distances to the wheels. The lock diff's correction effect is weakened if weight is transferred to the other two wheels, or inside tire slips or lifts up that no longer slow the outside wheel down.Third is that a tire has limited traction circle, that the amount of lateral and tangential grip has to trade off before both suffers. By adding tangential thrust, it would lower the amount of lateral forces than open(unlocked) wheels, subsequently upsets the front and back balance.
slip is the difference in speed between the left and right wheel on an axle.a limited slip diff prevents one wheel from going faster than the other.this improves handling by making it so the wheels on an axle are linked together, but not locked together.most cars have an open diff, which allows both wheels to spin independently. this is fine normally but in hard cornering or uneven terrain, if one of the drive wheels comes off the ground or loses grip, all the power of the engine will take the path of least resistance and spin only that wheel instead of both at once. this leads to bad and unpredictable handling as well as unreliable performance offroad. a limited slip diff solves this problem.
>>28120753>>28120755based info dumperquestions:if i had an AWD car with an LSD on both ends, would increasing the preload on either diff increase mechanical understeer?Would increasing the rear preload increase power oversteer?Would increasing front preload increase power understeer?
