I am
NOT a tyre engineer. But I understand some of the complexities and theory. It's interesting stuff.
There is nothing "wrong" with the steering geometry. It has been designed in this way because that is what market research told Jaguar their customers wanted.
You've bought a Sports 4x4 (or whatever the market moniker is today).
F-Pace customers didn't want a Land Rover Defender, as they want something that looks better. But more importantly they want something that
drives better on the road - where they will be 99.9999% of the time - and they want 4WD for extra security. They want the car to be safe and composed at 150+ mph. In fact they want it to
handle predictably at 150+ mph and still provide plenty of steering feedack.
They want it to be a big comfy compliant-riding family carrier at one point,
and act like a "sports car" when the family and dogs have been kicked out and Dad/Mum is going on a solo drive along their favourite piece of twisty tarmac.
Which is why they spent so much time at the Nurburgring fine tuning things. (Like most other manufacturers). The F-Pace buyer demographic wants a large comfortable 4x4 family super-sports car.
This is all well and good, but gives the designers some headaches, and compromises have to be made somewhere. One of those is in the steering geometry.
The F-Pace is my wife's car (and the family car). It is a superb piece of kit.
My car is a Lotus. If you get upset at the low-speed steering scrub on your F-Pace, you would be very very angy indeed at the low-speed steering scrub on my car. :evil: You'd be
apoplectic as it is terrible. Particularly in reverse. The front tyres chung-chung-chung as you go anywhere near full lock in reverse. It is not pleasant, but it does this for a reason.
And that reason is that the Lotus chose to set the car up with "Anti-Ackerman" steering geometry. Essentially (and
very simplistically) the engineers / marketeers have placed high-speed handling / grip / feedback very high up the priority list. They've accepted that this will bring compromises at manouvering speeds.... can't have your cake and eat it mate.
The F-Pace isn't as extreme, but to get all the traits listed above for the F-Pace buyer demographic, they have clearly set the car up with the ackerman steering angles biased towards high-speed capability.
If you are interested in the topic, you might want to watch a couple of videos. Boring techy vids, possibly a bit too long for your needs, annoying Aussie accent (sorry Aussies
) but hey... You need to watch them in order as the second vid assumes you understand the theories covered in the first.
Tyres and Slip Angles
Ackerman Steering (Pro and Anti)
Speaking about the 22" wheels (as that's what we have on ours) - the Pirelli P-Zero's are clearly a performance-biased summer tyre. They have been chosen to provide the high levels of grip, and immediacy of response that the F-Pace demographic want. Comfort/compliancy is compromised in favour of these factors. Because that is a compromise the F-Pace demographic are prepared to make. The rubber compound has been selected to optimise their performance capability - so they don't overheat when you find yourself on a clear 10-mile stretch of deserted tarmac when out for a summer run in the Highlands of Scotland. That was a nice run....
Unfortunately this means they don't work well at low temperatures. The compound is hard and unyielding as you get down towards 5DegC so it struggles to key into the surface of the road, and the sidewalls don't flex as they would in warmer weather when you apply steering loads / slip angles to the tyre.
On a hot summer day you can reverse on full lock and feel a little squirm from the wheel.
On a cold winter day you reverse on full lock and get some skipping from the tyres - they cannot follow the slip angles the steering geometry is requesting.
Stick a set of cross-climate tyres on. Hey presto - much reduced low-temperature skipping.
We just fitted Vredstein WintracS tyres to our F-Pace. Immediately all low-temperature skipping was completely banished. You don't even feel any "struggle" from the steering rim. These tyres remain sufficiently compliant of sidewall and adequately keyed into the road surface that this trait does not appear.
People increasingly want everything without compromise. Fast but frugal. Comfortable yet agile. Luxurious but cheap. Big but light. Tyres that perform well in hot and cold, in dry and wet conditions, on tarmac and snow and ice and mud, and sand. Car designers these days pull off some pretty impressive magic tricks, but as the great Scotty (allegedly) stated - you cannae change the laws o physics.