4.6is = Active Steering?

[ZsX5o3]

been searching & searching but still can't find a definitive answer on this. if it's right in front of my face feel free to flame me

I may be trading my 3.0 in a couple of weeks on a 4.6is, and there's only one thing holding me back. The steering. I really prefer the tight, hard steering on the 3.0 where it feels more stable, and sharp even at low speeds. yet on the 4.6is the steering is very soft, I suppose I could adjust to it but I don't know if I like it.

So, does the 4.6is('02-'03) have active/adaptive steering? If so, can it be turned off? If you have it how do you like it in comparison? What are the advantages?

thanks for any help on this.

[mrkbbd]

it has variable steering where it is really soft a low speed and hard at high speed or in times of "real" driving

[mrkbbd]

it can't be disabled, but i like it, especially in the city

[LeMansX5]

Active Steering
When BMW first introduced Active Steering to the market in 2003, our drivers weren't the only ones who were impressed. It received the Innovation Award of German Industry, too. The technology allows for a variable steering ratio based on your speed. At low speeds, steering is nimble (10:1) for easy navigation in tight spaces. At high speeds, greater movement of the steering wheel is required to turn the front wheels the same amount (18:1), for increased stability. Most car companies split the difference with a constant 14:1 ratio, but we're not ones to compromise - even with our steering ratio.

[AzNMpower32]

I believe the 4.6is still had the old-style recirculating ball type steering (as opposed to rack-and-pinion); I remember driving someone's X5 4.6is at the DC meet which was ages ago. It really is light and a vague.

It's definitely not Active Steering since that wasn't introduced until the E70.

[LeMansX5]

Originally Posted by AzNMpower32

I remember driving someone's X5 4.6is at the DC meet which was ages ago. It really is light and a vague.

That was a ekaz's 4.8is you drove with Supergreg at DC of the three 4.8is there. I moved from 4.4 to 4.8is and its much better than 4.4 steering. I think its sporty than vague.

[Weasel]

The only difference in the steering system on the 4.6is compared to the 3.0/4.4's is actually in control programming of the dsc control module. The variable output valve on the pump and pressure bypassing valve on the rack are controlled electronically by the DSC, and are set to different specs for easier turning at idle, but still has a real tight controlled feeling at high speeds. Other than that, the pump, steering rack, lines etc. are all the same part #'s as the other X5's. The active steering systems on the newer BMW's have a motor driving a planetary gear setup in the rack to adjust output ratios at different speeds, and can not be turned off without permanent faults.

I understand what you are looking for with the handling aspect, and can tell you the steering of the 4.6is is definitely the better option.

[vinuneuro]

Weasel, isn't the 3.0's assist rpm based?

What's the input for the Servotronic racks? Is it torque/slip or vehicle-speed based?

[Weasel]

The pressure assist is speed based, not rpm based. Controlled by controlling valve positions. Also the teeth on the cross bar in the rack are different widths from the center towards the ends... this is becoming hard to describe as how involved our steering systems are, so I am geting tempted to scan some pages from the "chassis dynamics/undercar technologies" books obtained during training. But I can be lazy... Any specific areas of the steering system you need info on?

[ZsX5o3]

wow that's a lot of impressive info, weasel. So the steering is adaptive, but it isn't the BMW Active Steering system?

Also LeMans, could you tell me why it's sportier? Wouldn't it feel less responsive? I really want to believe its better