Front wheel drive XC60 with VEA engines - traction in wet?

[GJB]

Have had 3 D5 since 2004 and the one in my XC60 with P* is definitely the smoothest drive of all I am hoping this will continue with my latest purchase.

[RoyMacDonald]

Originally Posted by Agouti

Any evidence to support 50/50 torque balance? I would be highly surprised if they did that under power as it would lead to heavy understeering. Typically you would expect to see more like 30/70 to account for weight shifting and to overcome the natural understeer and keep the car neutral. I would expect the balance to be adjusted based on speed, throttle, steering angle, yaw sensor, and traction feedback not by any sensor estimation of whether the car is near some Apex or at some round figure like 50/50. I think you might be getting confused with weight balance.

To be honest I would be surprised if the powered delivery was anywhere near that sophisticated anyway. From what I have seen there is selective differential lockup plus stability and traction control which is still a long call from torque control like, say, a Tesla would have.

When I said sensors I was trying to keep it simple. I meant they feed the information back to the computer and it adjusts the AWD to suit the incoming information. You brake before a bend start to accelerate and turn the wheel the sensor in the steering wheel sends a message to the electric motors in the steering rack and the wheels start move in the direction you have asked for. The sensor on the accelerator pedal sends a message to the computer to accelerate the car. As the car turns the yaw sensor and sensors in the wheels pick up how much each wheel is gripping. The AWD transfers power to the rear as you start to turn and also to the side that the weight of the car is thrown to as those wheels have more grip because of the g force acting on the car sensed by the yaw sensor. It will regard apex as when you stop moving the steering wheel but are still turning and will have moved smoothly to 50/50 by then. As you start to straighten the steering rack gets the message and moves accordingly and the AWD shifts back to 90/10 and both sides of the car. Bit difficult to describe it as so much happens at the same time and in milliseconds. 4C adds a whole other layer of instructions from the sensors in the adjustable shocks. There are a vast number of sensors and half a dozen computers involved in every thing a modern car does.

How it works and the power balance is well documented by Volvo on the Clubs web site. I have a whole load of PDFs but they are too big to post on a forum message.

Heard today that Tesla have got a new battery out and the 0 to 60 time is down to 2.5 seconds. Awesome.

Roy

[Tannaton]

Originally Posted by Chief inspector

The wet traction from the FWD VEA is as good as any FWD car and better than any RWD.
H

I'm sorry but it is not. The longer travel, softer suspension coupled with economy biased SUV tyres means this is a chink in its armour. I wish it was as I've just got one but it's not.