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      06-26-2013, 04:14 PM   #13

Drives: 2013 M3
Join Date: Jun 2010
Location: Vero Beach, FL

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I'm optimistic about the future of EPS. Chris Harris really liked it in the latest GT3 preview.

Quoted from another thread:

Originally Posted by bradleyland View Post
EPS has the potential to be far better than hydraulically boosted steering assist.

Hydraulic systems use a pressure differential valve and a hydraulic ram to assist in steering. The pressure differential valve is calibrated to match input torque (how hard you twist the steering wheel) with assist, courtesy of pressurized hydraulic fluid fed to a ram. You can vary the assist by varying the pressure in the system, but the whole thing is more or less locked in to a set of parameters established by the mechanical design of the system.

Not to mention, all hydraulic systems have a large amount of parasitic drag. Moving the hydraulic ram requires additional effort above and beyond the effort required to turn the wheels.

An electronic system drives the steering components directly, and has far less parasitic drag when it's not offering assistance. In theory, you could turn off EPS through software, and you'd have manual steering with less additional effort than what would be required by disabling a hydraulic system. This means that EPS offers a much greater range of assist, and should (in theory) result in better overall steering feel.

The problem with current EPS systems is in the software. The upside is that software can be changed. I'm kind of surprised we haven't seen more software tuning for EPS "tuning", much like we do ECU tuning. The system has the potential to far exceed hydraulic systems, but we're stuck waiting on the software engineers to figure it out, and the execs to approve more aggressive tuning.
His: 2013 ///M3 - Interlagos Blue Black M-DCT
Hers: 2013 X3 28i - N20 Mineral Silver / Sand Beige / Premium, Tech
Past: 2010 135i - TiAg Coral Red 6MT ///M-Sport