All this does is to convert a loose open diff into a spool diff by varying degrees.strad wrote:Picture a posi rear end with it's clutch pack, but with the ability to hydraulically apply those clutches when you want instead of when a wheel slips. Ever drive something with a nice new tight clutch pack, oh say on the freeway for a distance and when you get off and make a turn at the end of the off ramp you skip a bit around the corner because the clutches have swollen with heat and locked up like a spool? Think of being able to do that to varying degrees by applying pressure..Now you can have pressure on the inside wheel and MAKE the car want to turn in.
Increasing diff locking will increase under steer.
It will do so with increasing tyre wear and it does not give torque vectoring from the torque source.
Fully locked the this diff will give a 50 50 torque split.
Fully open it will give a 50 50 torque split less any output torque differences caused by planetary design, less any loss of torque due to any wheelspin on one or both sides. It is the wheel rpm which slowly becomes the same for both sides as the locking increases to fully locked, that causes the under steer, it has nothing to do with torque vectoring.
The traction of the turned front tyres ends up trying to turn the car by ripping off the tread of the rear inside tyre.
The more the clutch pack applies and begins to lock the axle as a spool, the more the car will under steer.
The locking will help balance energy harvesting through the KERS system and traction loss/wheel spin will be reduced across the axle but at the expense of difficult to control tyre wear and mechanical set up problems.
Trying to compensate with suspension settings biased to stiff front soft rear to reduce under steer and rear tyre wear, will result in unpredictable turn in, front inside wheel lifting and front inside wheel lock ups under braking.
Somebody should change their gearbox designer
The only reason why this heath robinson result occurs is because aero demands always outweigh mechanical or powertrain.
and aero forces mask out most of these kinds of effect.
