[Lotus7]

There has got to be the basis for a Sociology PhD dissertation buried in this thread. How a simple question about [how] “the stock suspension handles on the curves” (Original Poster quoted) can turn into a pissing contest, references to one’s mother, Vestal Virgins, and auto-flushing toilets in only (44) posts is simply amazing. This thread says WAY more about people than it does about the X3’s suspension behavior.

It’s a real “hoot” to witness how defensive people can be about their totally subjective opinions.

Isn’t the Internet wonderful?

Soapbox Mode OFF.

[soj]

Here's my assessment:

- Steering:
-- MSport Package - moderately firm (A bit looser than E90 w/sports package)
-- Non-mSport - Moderately loose (A LOT looser than E90 w/sports package)

- Suspension
-- MSport - Moderate (comparable to E90 w/o sports package)
-- non-MSport - Moderate (comparable to E90 w/o sports package)

This is all done on cars with no DHP.

[clivem2]

Originally Posted by soj

Here's my assessment:

- Steering:
-- MSport Package - moderately firm (A bit looser than E90 w/sports package)
-- Non-mSport - Moderately loose (A LOT looser than E90 w/sports package)

- Suspension
-- MSport - Moderate (comparable to E90 w/o sports package)
-- non-MSport - Moderate (comparable to E90 w/o sports package)

This is all done on cars with no DHP.

MSport and non-MSport suspensions in the US are same aren't they? Softer than in the rest of the world with the standard spec and certainly softer than a "real" MSport setup (rest of the world or international).

[soj]

Yes. But I'm in the US so can only speak to US X3s. Softer than a 3 series with sport. Similar to 3 series without sport.

[Harplayr]

Has there been any discussion of a stronger anti-sway bar to stiffen things up laterally? Does it even have one?

I love the “ride quality” of the stock suspension (non-sport) as far as handling bumps, but find it a bit soft in strong winds.

[Vintage]

Originally Posted by Penso di no

See now, where I grew up, that kind of a statement has a natural response involving agreement confirmed by experience, comparison to your mother, etc. But I won't go there.

That's quite a schnitzer you have there, chilly. [that kind of statement could get you in trouble in my neighborhood, too]

Motor on...

again, just kidding around with fellow enthusiast

[Dukat]

Anyone know if it's possible (with Dynamic Handling Package) to stiffen up the suspension and steering without altering the transmission response?

I'd like to be able to have the sportier feel without dropping mpg on my daily commute.

[Le Chef]

Originally Posted by Dukat

Anyone know if it's possible (with Dynamic Handling Package) to stiffen up the suspension and steering without altering the transmission response?

I'd like to be able to have the sportier feel without dropping mpg on my daily commute.

Go into "Vehicle Settings" and you can figure "Sport" and "Sport +" to your hearts content. Then unless you need Vestal Virgins to move the button for you, you just press the "Sport" button and it will change to your settings.

[Penso di no]

Originally Posted by VintageBMW

again, just kidding around with fellow enthusiast

Likewise.

[Lotus7]

Originally Posted by Harplayr

Has there been any discussion of a stronger anti-sway bar to stiffen things up laterally? Does it even have one?

I love the “ride quality” of the stock suspension (non-sport) as far as handling bumps, but find it a bit soft in strong winds.

The X3 (F25) has "humongous" F & R anti-sway bars. With a relatively high center of gravity, there's only so much you can do with anti-sway bars. Too stiff and the (high-CG) vehicle still has a lot of lateral roll, but the inside wheels lift. Although it doesn't "feel" great to have significant body roll, sometimes it's the best way to achieve maximum steady state cornering power (lateral acceleration). If the dampers are stiff enough, you can allow reasonable roll and still have decent transient handling. I think the X3 in “Sport” mode is pretty decent (damping-wise). In “Normal” it's certainly under damped for best possible handling, but IMHO it's a very good ride/handling compromise setting.

[Harplayr]

Originally Posted by Lotus7

The X3 (F25) has "humongous" F & R anti-sway bars. With a relatively high center of gravity, there's only so much you can do with anti-sway bars. Too stiff and the (high-CG) vehicle still has a lot of lateral roll, but the inside wheels lift. Although it doesn't "feel" great to have significant body roll, sometimes it's the best way to achieve maximum steady state cornering power (lateral acceleration). If the dampers are stiff enough, you can allow reasonable roll and still have decent transient handling. I think the X3 in “Sport” mode is pretty decent (damping-wise). In “Normal” it's certainly under damped for best possible handling, but IMHO it's a very good ride/handling compromise setting.

What would you suggest to improve tracking and crosswind performance?

[Dukat]

Originally Posted by Le Chef

Go into "Vehicle Settings" and you can figure "Sport" and "Sport +" to your hearts content. Then unless you need Vestal Virgins to move the button for you, you just press the "Sport" button and it will change to your settings.

I meant is it possible to configure suspension & steering without modifying the transmission? Using the default Sport/Sport+ mode affects everything. Would be great is there was an option to select which components are affected.

I haven't gotten my car yet so I can't explore the Vehicle Settings menu. 2 more months.

[Penso di no]

Originally Posted by Dukat

I meant is it possible to configure suspension & steering without modifying the transmission? Using the default Sport/Sport+ mode affects everything. Would be great is there was an option to select which components are affected.

I haven't gotten my car yet so I can't explore the Vehicle Settings menu. 2 more months.

What you're asking for is exactly what Le Chef was saying. If you have DHP then you have exactly the kind of control you're asking for (using iDrive). The only thing you can't change is the default setting.

[Lotus7]

Originally Posted by Harplayr

What would you suggest to improve tracking and crosswind performance?

Not an easy answer.

Warning: Long, rambling post. Read at your own risk!

Since I've been fairly satisfied with the crosswind performance I haven't given it much thought. The car does have a substantial side area, and it clearly is slightly deflected by cross winds, but really, I haven't been bothered by it and think it's typical or even “less then typical” for a vehicle of its size and height (maybe my expectations aren’t as high as yours). I’ve actually been impressed with the bump-steer response (steering changes as the suspension is deflected) and have found it to be very neutral. I’ve driven a lot of cars that are much worse.

However, in my experience with other cars, I’ve occasionally been utterly amazed by how much tire types and even moderate tire pressure changes can affect both crosswind sensitivity and tracking. I had a fairly-quick, modified Audi A4 2.8 that originally had max-performance Dunlop summer only tires. I thought it handled pretty well. Well before the Dunlops wore out, I got a set of German Goodyear F1 GSD3’s. (Same size as the Dunlops) The transformation of the car was amazing: much better tracking (the car went where I pointed it without any hesitation), significantly better ultimate cornering limits (confirmed by a 3-axis recording accelerometer borrowed from my race car), and a more linear steering feel. I immediately bought a set of the GSD3’s for my wife’s Subaru Legacy GT turbo, which had Yoko all-seasons. The F1 tire improved the Legacy also, but not nearly as dramatically as the Audi, even though the Subi OEM tires were not “as good” as the Audi’s original Dunlops. As we all know, the way a vehicle handles is a sum of a large number of factors and changing one may make a difference on one vehicle, but may not make much of a change on another.

My 35i has only the OEM 245/50-18 Pirelli P7 All Seasons run-flats, which are certainly not an extremely high performance tire. With those tires I find the tracking pretty good up to about 8/10s of the vehicle’s maximum cornering limits. At that point they begin to “wash-out” at both ends of the car. It’s very obvious as you loose the ability to make steering corrections with the steering wheel and have to use throttle modulation to control the understeer as the car drifts wide.

With the car unloaded, I run the P7’s at 35-psi front and 38 rear. A little more pressure, especially at the front would probably help raise the ultimate cornering limit, but would probably make the car a little more sensitive to cross winds and would stiffen the ride a little too much for my taste. A little more [pressure] at the back may reduce the cross wind sensitivity, but at the expense of a poorer, “bouncier” ride when the vehicle is unloaded. As it is, even with the all-season P7’s the X3 handles better than probably 90% of the other vehicles on the road and will take most corners at well above the posted speed limit or suggested speed. It’s my everyday driver and I don’t find it lacking, even in “spirited” driving. Of course my racecar handles much better, but it won’t hold (5) passengers or 55 cubic feet of “stuff”, and the ride is beyond brutal (2 inches of suspension travel, 2-inch high-pressure, inboard Bilsteins and 450 lb./inch H&R springs).

As far as I can tell, camber is fixed on the F25 chassis and can only be changed in increments by replacing steering components. On the other hand, toe-in IS adjustable. On most all all-wheel drive vehicles, front toe-in is fairly critical, but small changes can be done with no ill effects to tire wear. I suspect, but have no first-hand knowledge, that a small toe-in change may make a big change in the “on center” feel of the X3 and the tracking at low to moderate lateral loading (cornering). I’ve made changes on some light weight race cars going from 1/8 inch toe-in to no toe-in and have found the car’s initial tracking to become much more responsive and “twitchy”. Going the other way will increase the self-centering and decrease sensitivity to cross winds. Some racers will actually set up their front ends to a slight tow-out. That makes for a car with very quick reflexes; it turns immediately, but is not something anyone would want to drive on a highway (if you take your hands off the wheel, the car will try to turn one way or the other very quickly). The point is, very small toe-in differences can dramatically affect the steering “feel” and can easily account for differences in apparent handling between (2) otherwise identical cars. It might be beneficial to increase the front-end toe-in by 1/16 to 1/8 inch to see if it reduces the crosswind sensitivity you’re feeling. However, (there’s always a catch), you may not like the increased resistance to get the car to move off center and to turn.

I have no idea of what the toe-in spec. for a X3 is or what the tolerance range is.

Told ya it was rambling!

[Dukat]

Originally Posted by Penso di no

What you're asking for is exactly what Le Chef was saying. If you have DHP then you have exactly the kind of control you're asking for (using iDrive). The only thing you can't change is the default setting.

Excellent, thanks!

[Penso di no]

Originally Posted by Lotus7

...
Told ya it was rambling!

Perhaps, but super informative. Thanks!

[chillychan]

Originally Posted by Penso di no

Perhaps, but super informative. Thanks!

Agreed. Thanks!

[Harplayr]

Originally Posted by Lotus7

Not an easy answer.

Warning: Long, rambling post. Read at your own risk!

Since I've been fairly satisfied with the crosswind performance I haven't given it much thought. The car does have a substantial side area, and it clearly is slightly deflected by cross winds, but really, I haven't been bothered by it and think it's typical or even “less then typical” for a vehicle of its size and height (maybe my expectations aren’t as high as yours). I’ve actually been impressed with the bump-steer response (steering changes as the suspension is deflected) and have found it to be very neutral. I’ve driven a lot of cars that are much worse.

However, in my experience with other cars, I’ve occasionally been utterly amazed by how much tire types and even moderate tire pressure changes can affect both crosswind sensitivity and tracking. I had a fairly-quick, modified Audi A4 2.8 that originally had max-performance Dunlop summer only tires. I thought it handled pretty well. Well before the Dunlops wore out, I got a set of German Goodyear F1 GSD3’s. (Same size as the Dunlops) The transformation of the car was amazing: much better tracking (the car went where I pointed it without any hesitation), significantly better ultimate cornering limits (confirmed by a 3-axis recording accelerometer borrowed from my race car), and a more linear steering feel. I immediately bought a set of the GSD3’s for my wife’s Subaru Legacy GT turbo, which had Yoko all-seasons. The F1 tire improved the Legacy also, but not nearly as dramatically as the Audi, even though the Subi OEM tires were not “as good” as the Audi’s original Dunlops. As we all know, the way a vehicle handles is a sum of a large number of factors and changing one may make a difference on one vehicle, but may not make much of a change on another.

My 35i has only the OEM 245/50-18 Pirelli P7 All Seasons run-flats, which are certainly not an extremely high performance tire. With those tires I find the tracking pretty good up to about 8/10s of the vehicle’s maximum cornering limits. At that point they begin to “wash-out” at both ends of the car. It’s very obvious as you loose the ability to make steering corrections with the steering wheel and have to use throttle modulation to control the understeer as the car drifts wide.

With the car unloaded, I run the P7’s at 35-psi front and 38 rear. A little more pressure, especially at the front would probably help raise the ultimate cornering limit, but would probably make the car a little more sensitive to cross winds and would stiffen the ride a little too much for my taste. A little more [pressure] at the back may reduce the cross wind sensitivity, but at the expense of a poorer, “bouncier” ride when the vehicle is unloaded. As it is, even with the all-season P7’s the X3 handles better than probably 90% of the other vehicles on the road and will take most corners at well above the posted speed limit or suggested speed. It’s my everyday driver and I don’t find it lacking, even in “spirited” driving. Of course my racecar handles much better, but it won’t hold (5) passengers or 55 cubic feet of “stuff”, and the ride is beyond brutal (2 inches of suspension travel, 2-inch high-pressure, inboard Bilsteins and 450 lb./inch H&R springs).

As far as I can tell, camber is fixed on the F25 chassis and can only be changed in increments by replacing steering components. On the other hand, toe-in IS adjustable. On most all all-wheel drive vehicles, front toe-in is fairly critical, but small changes can be done with no ill effects to tire wear. I suspect, but have no first-hand knowledge, that a small toe-in change may make a big change in the “on center” feel of the X3 and the tracking at low to moderate lateral loading (cornering). I’ve made changes on some light weight race cars going from 1/8 inch toe-in to no toe-in and have found the car’s initial tracking to become much more responsive and “twitchy”. Going the other way will increase the self-centering and decrease sensitivity to cross winds. Some racers will actually set up their front ends to a slight tow-out. That makes for a car with very quick reflexes; it turns immediately, but is not something anyone would want to drive on a highway (if you take your hands off the wheel, the car will try to turn one way or the other very quickly). The point is, very small toe-in differences can dramatically affect the steering “feel” and can easily account for differences in apparent handling between (2) otherwise identical cars. It might be beneficial to increase the front-end toe-in by 1/16 to 1/8 inch to see if it reduces the crosswind sensitivity you’re feeling. However, (there’s always a catch), you may not like the increased resistance to get the car to move off center and to turn.

I have no idea of what the toe-in spec. for a X3 is or what the tolerance range is.

Told ya it was rambling!

Thanks Lotus.

Maybe I should have expounded more on what I’m feeling and comparing it to.

I currently have a 2011 F25 X3 28i without sport package (17” wheels stock rft tires at recommended pressure). My previous ride was a 2010 X3 3.0i non-sport with 17” Michelin Primicy MXV4 tires. It did have the variable steering package. That car handled crosswinds better than my F25 and wasn’t as sensitive to the crown of the road. It tracked much straighter.

I live in wind-farm country strong winds are the norm. It is not at all unusual to have winds exceeding 25mph and we often get higher winds.

What I’m noticing is that because the car is following the crown more, I’m always tensioning the steering wheel to combat the minor drift. On less windy days, it’s no problem---the “drift” is minor and just wants to follow the crown a bit more than my old X3 did. When the wind kicks up the steering feels a bit more “dead” and not nearly as “planted” as my old X3.

So taking into account your post, maybe a slight alignment adjustment might bring it on par with the old X3?

What would you try first….
Alignment adjustment
Tire pressure
Change tires
Change wheel size (currently 17”)

[Lotus7]

Originally Posted by Harplayr

Thanks Lotus.

Maybe I should have expounded more on what I’m feeling and comparing it to.

I currently have a 2011 F25 X3 28i without sport package (17” wheels stock rft tires at recommended pressure). My previous ride was a 2010 X3 3.0i non-sport with 17” Michelin Primicy MXV4 tires. It did have the variable steering package. That car handled crosswinds better than my F25 and wasn’t as sensitive to the crown of the road. It tracked much straighter.

I live in wind-farm country strong winds are the norm. It is not at all unusual to have winds exceeding 25mph and we often get higher winds.

What I’m noticing is that because the car is following the crown more, I’m always tensioning the steering wheel to combat the minor drift. On less windy days, it’s no problem---the “drift” is minor and just wants to follow the crown a bit more than my old X3 did. When the wind kicks up the steering feels a bit more “dead” and not nearly as “planted” as my old X3.

So taking into account your post, maybe a slight alignment adjustment might bring it on par with the old X3?

What would you try first….
Alignment adjustment
Tire pressure
Change tires
Change wheel size (currently 17”)

I'd certainly try the easiest thing first i.e.; the tire pressure. The "Owner's Manual pressure" (not always the same as the latest recommendation on the door jamb) for the 225/55R17 (102H) tires is 32F-32R and
for the 225/60R17 (99H) tires is 32F-35R
for "partial loads" and up to 35/41 for full loads.

It's easy to try higher pressures and to experiment with the pressure differential. Just be sure to always check/change pressure when the tires are completely cold and at approximately the same ambient temperature.

I'd probably start at 34 psi F and 37 R. (cold) If you notice any improvement you might try as much as 39 in the rears.

The next easiest thing to try would be to first check the wheel alignment to be sure it's in spec. If the front toe -in reading is toward the low end of the range you might have the value increased. I'd also check the rear toe in. I don't know if the rear of the X3 has a continuous adjustment for toe-in as the front does, or if it uses shims like some cars (never took a close look), but it should be checked. The rears are typically set for very low toe-in, if any. If the rear toe-in is negative (actually showing some toe-out, it can cause excessive wind sensitivity and constant "hunting" when you're trying to drive straight.

On my 35i, the on-center feel and straight line tracking is not "great" and it took a little while for me to adjust to it mainly because my other cars have a lot of self centering action and no power steering. Going from a two ton-plus X3 35i P/S, P/B, full auto transmission to a 1/2 ton Lotus with a manual 5-speed, a racing clutch, manual steering that's twice as fast as the X3 and manual 4-pot racing brakes that take 5X the pressure to stop takes a major mental adjustment and lot's of concentration, but going back the other way is actually harder for me. My wife always has a stifled laugh when I jam my left foot to the floor and grab for the shift lever if I have to make a quick stop.

[tank531]

I am not going to comment on the original thread as a) I dont yet have an F25 b) the question is more subjecitve than most and c) I dont drive fast/on the limits or have much experience as other posters. However, to add fuel to the fire this thread has a very high repsonse rate just under 9% of readers have commented, far higher than most...............

[tank531]

....math correction meant to say 7% (must have been a metric to imperial conversion error)....

[sfax]

Originally Posted by tank531

I am not going to comment on the original thread as a) I dont yet have an F25 b) the question is more subjecitve than most and c) I dont drive fast/on the limits or have much experience as other posters. However, to add fuel to the fire this thread has a very high repsonse rate just under 9% of readers have commented, far higher than most...............

I've read it but not commented on it. Doh!