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Old 08-31-2012, 10:12 PM   #38 (permalink)
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Fusion - '16 Ford Fusion Hybrid SE
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Originally Posted by TheSGC View Post
I've decided to dump the power steering for now, from what I have read it takes too much power to operate (5-8.5 HP!).
I don't think an unloaded power steering pump takes nearly the power you think to run at a low speeds. For EV purposes, it would have to spin at the same speed as an ICE at idle. When unloaded (not turning on the steering wheel), the pump is simply moving fluid from the reservoir, through the pump, through the valving in the rack and back home to the reservoir. There is little to no restriction and very little energy required. I could see 5 hp at 6000 rpm (ICE speed) and fully loaded against a steering stop, but not unloaded at idle. Less than 1/2 HP, I would guess. Especially with an efficient treadmill motor doing the work. By comparison, your A/C pump will require 100X the energy to run.
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