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19 I-pace HSE Polaris/Fuji white with most options and a lot of accessories
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Jaguar wheels came in 18, 20 or 22. Not 19.

Tire aspect ratio and inflation pressures influence sidewall strength.
Sidewall strength influences cornering and handling.

"OEM" doesn't tell us anything since they offered multiple tire brands. If you really do have 19s, then it isn't anything supplied by Jaguar.
 

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Discussion Starter #22
My mistake. They are 20s. Sidewall strength influences corning and handling, certainly. My tires are Goodyear Eagle Sports, which is a pretty good all-season tire. However, no all-season will match a proper summer performance tire, so I believe the point is a bit moot, so long as tire pressure is to spec. I'll admit mine is a little low, by about 3 PSI all around, due to the cooling weather, but this body roll issue has been needling at me for over a year. That said, I will get some more air in my tires today. I have personally experienced a big difference in handling at the "comfort" pressure vs. "normal" pressure. More to the point: body roll is the issue I'm trying to resolve, which in not affected by tire choice or pressure.

I get that you want to be sure I'm not some rich guy who thinks he bought a fast car, doesn't know how to drive it, and doesn't know the important factors in handling. I assure you, I do. I've run various cars at various tracks for the past 15 years, and have been autocrossing off and on for many of them. I have "graduated" from Bob Bondurant's high performance driving school, attended numerous HPDE days, and am certified solo for the track. I am no race car driver, but track driving was very much a hobby of mine until acquired the I-Pace (I didn't walk away from the hobby because of the I-Pace, but because the thrill was gone - so I sold my 911 and bought the Jag, which is obviously more family- off-road, and environmentally-friendly than a 911). I do, however, still like to drive. Very much so.

In the course of pursuing my track driving hobby, I had the suspensions of two cars professionally modified (An Audi S5, then an Audi S4). Track-friendly tires were of course critical. Suspension mods are a fairly ordinary modification to ICE cars running springs (rather than air), hence my question to the forum. In no way do I expect the Jag to handle like a sports car, sports coupe, or sports sedan. At the same time though, I've been perplexed by the track coverage of the I-Pace in the media, as my car feels like it wants to tip over on a fast sweeping on-ramp. I do think my car could handle better than it currently does, if only its body roll could be contained. Steering feedback is surprisingly good. Acceleration out of corners is of course other-worldly. It's just what the chassis is doing at turn-in and mid-corner that is frankly a bit scary.

Now that that's out of the way, advice regarding my original question would be most helpful. From others' responses, it appears that my suspension isn't behaving the way it should in "dynamic" mode. Thank you!
 

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Discussion Starter #23
Hi smitty, we both have FEs, mine corners hard and flat as in the Laguna Seca video above. (y)

I have the 20" wheels & tires that came with the car. Front to rear weights are reported as 50%:50% so I am currently running 41 & 42 PSI for hills & country road driving on sealed roads in very good condition.

I just checked my infotainment screen app "Dynamic-i" it has been "Reset" to Factory Settings ie all 3 options are set to Dynamic (none are set to Comfort). The Dynamic-i App also includes a G Meter with max hold display that I have not used yet, but it may be helpful with your problem. On the Laguna Seca video the car is displaying the Dynamic-i app Lap Timer page, in pause mode.

Your body roll problems may be due to a Comfort option "set" in Dynamic mode or soft front tires or a faulty Adaptive Dynamics module.

Cheers, Steve
Thanks Steve! I started exploring Dynamic-i again yesterday. All settings are the same as Factory: Dynamic, Dynamic, Dynamic! All 4 tires are running a little soft due to the cooling weather, but I've had this notion that the Jag could handle better for a year, and only just decided to try and do something about it. More and more, it's sounding like a visit to the dealership is in order.
 

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Discussion Starter #24
I don't think it's an issue with being in comfort mode. Even in comfort mode, the car doesn't lean all that much. In dynamic, it's noticeably flatter, but not dramatically so.

Where are you, @smitty? Maybe someone nearby can see what's up while socially distanced?

It could be something weird with whatever 19" tires you're running. Damaged suspension. Alignment issue. With 20" all seasons, the car corners at least .85g and swallows bumps while doing so. I have done the same road in anger with an E60 550i sport, E60 528i, FRS, Forester, xA, Integra LS, Model X, Model 3 Performance, Spark EV, Fiat 500EV, 135i, and Z4. The only car from the list that gripped more confidently was the M3P on Michelin Pilot Sport 4S, but dear god was it a dull drive. Also my arms hurt because of the messed up steering effort. I've never had that happen before. But I digress. Your experience is quite different from mine.

I gotta get stickier tires for the FRS, but the rear is set up to slip no matter what.
WOW. Yeah, that's a huge difference from my experience, where there's major body roll in comfort mode, and pretty similar in dynamic. The suspension also tends to get pretty upset in certain conditions, causing the whole vehicle to jostle back & forth. I have tried to push the car around corners the way I did in my 911, modified S4 and modified S5 and some others - but it's spooky to me at higher speeds. I'm really starting to thing something is wrong with my stock suspension setup, rather than it needing modification. Thanks!!
 

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Discussion Starter #25
WOW. Yeah, that's a huge difference from my experience, where there's major body roll in comfort mode, and pretty similar in dynamic. The suspension also tends to get pretty upset in certain conditions, causing the whole vehicle to jostle back & forth. I have tried to push the car around corners the way I did in my 911, modified S4 and modified S5 and some others - but it's spooky to me at higher speeds. I'm really starting to thing something is wrong with my stock suspension setup, rather than it needing modification. Thanks!!

Oh, and I'm in Portland, Ore. And I mistakenly stated my Jag was wearing 19s. It's on 20s.
 

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Discussion Starter #26
I decided to play with the G-meter. I got lucky with perfect conditions (dry weather, no traffic), so was able to put the I-Pace through my favorite on-ramp test. In dynamic mode (steering, suspension and throttle all "dynamic"), with the G-meter on, the car put up 0.79G on my test on-ramp and hit 104mph before hitting the freeway (where I always decelerate to roughly legal speeds). That's better than I've ever seen it do. With the body waggling around, I've generally only gotten it up around 90. The 911 and S4 could both do better at 115mph(!) and 111mph - but 104 is respectable in my book, especially for a heavy SUV thing - and it can do better. I let off the throttle more than I should have in the turn and regen set in. On the empty forested road to my house I put up 0.85G in a corner and could have gone much harder but for not wanting to kill anyone. If it were to behave like it has today, I could see it putting up at least 1.0G at the track without much trouble. That would be impressive, wearing all-season rubber.

So I dunno. Maybe I scared it into submission. Cornering has been noticeably flatter today in dynamic mode - not what I would call flat, but more like I expect it to be. Maybe running the G meter jogged the software into action. Almost believable, with the Jag's uber-buggy (but slowly improving!) software and all. Perhaps the software actually had the suspension in comfort mode in Dynamic-i despite the UI saying otherwise. Maybe my brain is failing me more than I even realize. Regardless, today marked the first on-ramp test where I wasn't disappointed. I'll keep testing, and see if I can hone in on what's happening. I'm bringing my son to a HPDE next month. Maybe the Jag needs to go too! See what it can do in autocross and on the track. --Tom
 

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Interesting. I do have the adaptive dynamics option. In dynamic mode, I find steering feel and throttle response to be better, but I find the suspension hardly changes at all. Lots of body roll. I wonder if I should take it into the dealer for a look..
I have the 20's and have them at 37 psi all around. In comfort there is body roll in cornering and coming out or making abrupt steering inputs you can feel it wallowing back and forth. In dynamic it is a BIG difference. Much less roll, feels flat but the major difference is that the back and forth wallowing is gone. The car settles much quicker. I don't really notice any difference in ride comfort, feels pretty much the same to me. Goodyear tires on my car and I'm surprised, they are pretty good with grip. Try upping your tire pressures a bit that might stiffen up the sidewalls if its too soft for you.
 

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I'll keep testing, and see if I can hone in on what's happening. I'm bringing my son to a HPDE next month. Maybe the Jag needs to go too! See what it can do in autocross and on the track. --Tom
One former I-Pace owner, McRat, took his I-Pace (20” all season Goodyears) to an autoX event, and the other driver’s had difficulty in beating his time.
 

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It's a hugely heavy car. It does not dance on the tip of a needle. It does have lots of grip and acceleration, handling bumps pretty well too. But it's no 911 or modified S4. Those can be made to corner much faster because they weigh much less.

The difference between dynamic and comfort are noticeable, but really not huge. The spring rates are still the same. The roll bars are still the same. It's just the shocks tightening up.
 

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Discussion Starter #30
It's a hugely heavy car. It does not dance on the tip of a needle. It does have lots of grip and acceleration, handling bumps pretty well too. But it's no 911 or modified S4. Those can be made to corner much faster because they weigh much less.

The difference between dynamic and comfort are noticeable, but really not huge. The spring rates are still the same. The roll bars are still the same. It's just the shocks tightening up.
True that! The car definitely does not dance. Autocrossing it should be interesting. I imagine it will drive like a bruiser due to the weight, but will squirt out of turns thanks to the electric motors. More or less the opposite of your FR-S, where you really have to (and can) carry speed through corners.
 

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I think the I-Pace can potentially handle much better than it does. As it is (I have the air suspension), the vehicle sways horribly in corners, even in "dynamic" mode. Anyone hear of installing sway-bars on the I-Pace, or other suspension mods that will help it hustle around corners? Thanks!
I’ve taken my I-PACE on many a SoCal windy canyons and switchback filled mountain roads and it has fared admirably.
 

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There is a huge difference between light and heavy car handling. A heavy, well-suspended, low COG EV can have a ton of grip and give a lot of confidence thanks to relatively low body roll. However, it's not going to change directions as happily or nimbly as a light car. Nor will it brake the same way. With prper race pads on the FRS, I could brake very late and very hard compared to most other cars at the track, still staying out of ABS, even as I could not keep up in the corners on my Prius tires and with the tail-happy, less grippy suspension of the early FRS.

I can go much faster in the IPace, probably even mid corner, stock vs stock, but the FRS was forgiving to ham handedness, even fun that way. That kind of roughness just makes the I-Pace wallow like a whale.
 
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