terps

U.S. brochure:
http://f10.5post.com/forums/showthread.php?t=405980


Looks like it's the full thing, with all color swatches, options, specs, etc.

Some good reading for the porcelain throne

Camersson

Thank you thank you thank you! I have been searching high and low for this.

vkhong

According to the brochure, this is a standard option across 528i, 535i and 550i:
(1) Vehicle-speed-sensitive variable-assist (Servotronic), variable-ratio power steering

This is an available option on 535i and 550i:
(2) Integral Active Steering with Servotronic power assist (requires Dynamic Handling Package)

I understand (2). I am curious about (1). I was told by a factory rep that all F10 have electro-mechanical Active Steering. Is this true?

I currently have an Active Steering-equipped E60 and would like the same in an F10, without having to opt for the IAS.

Rudy

I picked up the printed version of this brochure just yesterday...the only difference is that the printed version has an multi-page insert on how the steel "balls" sculpture used in the ads works...

Here's a [clean] .pdf copy you can download directly from this thread:
F10 catalog (US).pdf

hinckley

I noticed the same thing and believe the "variable ratio" part of (1) is misstated. Similarly, I noticed that the description of the black panel instrument display is incorrect.

cobradav

I believe they are correct. BMW employes variable ratio steering in all its cars with or without "Active" steering. It simply means they use a rack-and-pinion gearset that has a different tooth pitch (number of teeth per inch) in the center than it has on the outside. This makes the car respond quickly when starting a turn (the rack is near the center), and also reduces effort near the wheel's turning limits.

With active steering they add a planetary gearset approximately in the middle of the shaft that varies the steering wheel lock to lock ratio based on speed. The lower the speed the less turns lock to lock (also a varying ratio but different than the rack and pinion varying ratio).

Rudy

cobradav's theory may be correct but I'd like to speculate even more...

On the F10, (and unlike the E60), the "Integral Active Steering" includes steerable rear wheels. It may be possible that active steering as we know it on the E60 (front wheel variable ratio only) may be a standard option now and adding AS to a car adds the rear-wheel steering bits...

vkhong

cobradav's description of variable steering ratio certainly makes sense. I hope Rudy is correct on all F10 having standard Active Steering, with IAS being optional - this is what a BMW factory rep led me to believe.

Rudy

Keep in mind that AS (not IAS) being standard will piss off many people who think it detracts from the drivability of the car...

cobradav

Rudy, you are correct that in the F10 the IAS does include the Rear steering which does behave differently at different speeds as well (opposite direction at speeds under 30 and same direction over 50). But I also believe, but am not sure, that non-IAS F10/11 equipped vehicles are simply straight up E6x style non AS variable ratio steering, albiet possibly wiht some tweaks compared to E6x feel/ratio. And my thinking on this is swayed by the really fierce debate on E6x AS and its feel and operation in corners that some so vehemently oppose. I just do not think BMW would foist that on everyone without a choice which now in this case adds the rear steering in the IAS form. It should be able to be proven at the dealership by testing at
dead stop. IAS should be like 1.5 turns lock to lock and non IAS 2+ turns.