(I’m new to this whole thing) So, I was reading about EPS systems, and while reading, many articles say that an speed sensing EPS system only changes the amount of power steering assist depending on the speed. Now while also reading, I was wondering, does the speed sensing EPS system add steering weight at higher speeds (basically, does it start adding resistance at higher speeds)?
It doesn’t “add” anything, but simply provides less assist, giving the driver more “road feel”.
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I don’t know how anything would add weight, but picture yourself on a bicycle with an electric motor for assist. Pedaling up a hill and the motor kicks in. That would produce an assist. Or your BIL running along side and pushing you.
It “adds” in the sense that it increases the amount of effort required by reducing the amount of assistance.
Yes, I know it lowers the assist and makes it harder to turn, but from what other guys are saying, it doesn’t ADD artificial stiffening, it just lessens the amount of steering assist.
That is correct. If you’ve ever been driving at low speed and the engine died you know the wheel is hard to turn and that there’s no need to add resistance.
Well I was meaning more for higher speeds.
I guess it depends on what you mean by adding stiffness. If the lane departure warning is active you may feel a slight difference in the steering wheel as the “shaker” warning alerts you, but that’s on a very late model car with all the bells and whistles. Conventional electric assist steering has been around for a long time and doesn’t add any “weight”, just lessens the assist for better road feel. BTW, hydraulic power steering has been doing that for much much longer.
Yeah, most modern cars have the shaker.
Correctamundo
At higher speeds you don’t need as much help to turn the wheels so the power steering applies less boost. It doesn’t actually add resistance though.
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It depends on the intended market as well as the manufacturer. I rented a Corolla around 9 years ago whose steering felt the same whether it was around town or on the freeway. Right off the center, there was this constant amount of stiffness that did NOT change until it returned to center
The steering on my mom’s Honda Fit is the opposite of that Corolla. Our minivan, with lotus tuned suspension, has a steering feel similar to that of the Fit. Having steering wheel resistance that corresponds to cornering force is preferable because you can feel when the tires are about to loose their grip on the road. Also when you turn your head to check your shoulder, your fingers would let you know what the car is doing
That corolla might have been broken, actually. Reading a majority of forums seems to tell me that when steering feels the same, the speed sensing system is broken.
It doesn’t actually make it harder to turn. When the car is moving, friction functions as power assist for steering.
If you drive a car that doesn’t have power steering, the only time you really struggle is when the car isn’t moving, or when the car is moving slowly. If the car is moving at a reasonable speed, you might not notice the lack of power steering at all.
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Yeah, I know it doesn’t make it ‘harder’ to turn, but it just decreases the steering assist. Now, this gets me thinking: with speed sensing rack and pinions, does the steering feel like the same stiffness, or does it change stiffness? I am looking to buy a Lexus RC F, so this is why I’m asking. I want to know if the steering feels the same no matter how fast you are going, or if it gets easier to turn at lower speeds. I know that the Sport button would stiffen the steering up a bit.
Because it’s computer controlled, it can do whatever the programming tells it to do. The only way to know is to drive it, and see how it feels to you.
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Yeah, true.
Two words ( Test Drive ) and then you will have your answer .
I’m willing to bet that everything on a Lexus is so smooth that you never notice any difference. I never have on any of my cars, even the ones that had full time power steering.
Well, I wasn’t meaning the smoothness. The question has already been posted on Lexus Forums. I will now be inactive on this thread