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Old 05-10-2015, 12:13 PM
  #31  
Noah Fect
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Originally Posted by pap2828
had both....prefer the driving feel without it especially when going fast!
It does absolutely nothing when going fast.
Old 05-10-2015, 01:03 PM
  #32  
Archimedes
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Originally Posted by pap2828
had both....prefer the driving feel without it especially when going fast!


You mean when PSP isn't even active?
Old 05-10-2015, 01:07 PM
  #33  
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The 'feel' argument cracks me up. We're talking about parking lot speeds. You'd think some of you guys are sliding your cars into parking spots sideways…

OP, PSP doesn't make the steering overly light. It merely moderately increases the power steering assistance at very low speed and makes it easier to make tight turns in a parking lot. Unless you're competing in the world's slowest autocross on a regular basis, it's something you'd be wise to at least check out before you finalize your order. You'll know right away whether you prefer it or not. All personal preference.
Old 05-10-2015, 06:39 PM
  #34  
strumbringer
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I think it's purely a matter of personal preference. Neither with nor without should be a deal breaker.

Having driven both recently, I found I preferred the firmer feel of the car without it. Yes, at parking lot speeds. The initial feel of the steering sets the tone for the drive in some ways (for me). Having said that, I am pretty sure I would get used to the Power Steering Plus... but I didn't get it on my car because I preferred how the car felt without it.

Man, I miss hydraulic steering
Old 05-11-2015, 12:08 PM
  #35  
GrantG
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Originally Posted by strumbringer
Man, I miss hydraulic steering
Exactly - that's the option they should be offering (hydraulic pump driven by electric motor, so there is no performance or efficiency penalty with way more feel).
Old 05-11-2015, 12:50 PM
  #36  
NoGaBiker
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Originally Posted by Archimedes
The 'feel' argument cracks me up. We're talking about parking lot speeds. You'd think some of you guys are sliding your cars into parking spots sideways…

OP, PSP doesn't make the steering overly light. It merely moderately increases the power steering assistance at very low speed and makes it easier to make tight turns in a parking lot. Unless you're competing in the world's slowest autocross on a regular basis, it's something you'd be wise to at least check out before you finalize your order. You'll know right away whether you prefer it or not. All personal preference.
Don't know why it would crack you up that a person would want the car to feel a certain way at certain speeds. By definition, "feel" has nothing to do with performance, i.e. mentioning "autocrossing" and "sliding cars into parking spaces sideways" almost indicates a lack of understanding of what the term "feel" means. I'm sure you actually understand it and just got carried away.

For comparison, imagine a gearbox (and this really isn't far-fetched these days) that is a traditional clutched manual. Except that, because it's a little hard for people to work the clutch in a parking lot, when they're going slow and concentrating on getting into the spaces, the box becomes a PDK Auto and works the clutch for you via servos. Some people would welcome that assist; some of us would say, "Yuck! I want to clutch/shift/clutch my-own-dam-self, even in the parking lot. I like the way it feels."

I respond to the PSP in the same way. I prefer a slight bit of wrestling with the car at slow speeds. It reminds me of wrestling with actual unassisted and low-assist racing cars in the paddock. I like that reminder even in my street car. Every Porsche I've had prior to this one has had heavier, mechanical-feeling steering at low speeds. I wish this one leaned more in that direction. My bad for just listening to the SA and checking the box; should have considered more seriously. Hopefully it can be deprogrammed.
Old 05-11-2015, 08:41 PM
  #37  
Noah Fect
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Originally Posted by GrantG
Exactly - that's the option they should be offering (hydraulic pump driven by electric motor, so there is no performance or efficiency penalty with way more feel).
Wow, that's either a brilliant, trenchant comment or a forehead-slappingly dumb one. I'm not sure which, and I guess that tips it in favor of the former.
Old 05-11-2015, 08:43 PM
  #38  
GrantG
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Originally Posted by Noah Fect
Wow, that's either a brilliant, trenchant comment or a forehead-slappingly dumb one. I'm not sure which, and I guess that tips it in favor of the former.
That is the system used on all of the factory 911 race cars (GT3 Cup and RSR) as well as the McLaren road cars. The only downsides are a little added weight and expense, but big upside for driving pleasure and ability to know exactly where the limit is in all road conditions.
Old 05-11-2015, 09:12 PM
  #39  
Noah Fect
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Originally Posted by GrantG
That is the system used on all of the factory 911 race cars (GT3 Cup and RSR) as well as the McLaren road cars. The only downsides are a little added weight and expense, but big upside for driving pleasure and ability to know exactly where the limit is in all road conditions.
Seriously? It sounds utterly insane to introduce two lossy power conversions in one system. It would be really interesting to be proven wrong on this one.

Electric steering, like hydraulic steering, can by itself be tuned to deliver as much or as little "feel" as needed. It's hard to see an upside to doing both.
Old 05-11-2015, 09:28 PM
  #40  
GrantG
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Originally Posted by Noah Fect
Seriously? It sounds utterly insane to introduce two lossy power conversions in one system. It would be really interesting to be proven wrong on this one.

Electric steering, like hydraulic steering, can by itself be tuned to deliver as much or as little "feel" as needed. It's hard to see an upside to doing both.
Here are the specs for the 991 Cup:

http://www.porsche.com/usa/eventsand...911gt3cup-991/

Scroll down to Suspension, then Front Axle and you will see:

"Electrohydraulic power steering"

This refers to the system I described. They've been using this for years and continue to do so, even on the 991 Cup and RSR. If electric steering can be tuned to have as much feel as needed, then why has it never equaled hydraulic which itself is heavily filter compared to manual (which is not practical on the modern heavier cars with the wide front tires).

Here's some description and illustrations of the McLaren system:
http://www.edmunds.com/car-reviews/t...alkaround.html

Scroll down to:
"The MP4-12C uses rack-and-pinion steering, and McLaren engineers told me they wanted to use hydraulic power steering for its superior feel. But electric power steering would have helped engine-bay packaging and parasitic power loss by eliminating the belt-driven pump, the belt hardware itself and the need for long hose runs.

To get both benefits, McLaren fitted this electric-driven hydraulic pump (black), which feeds the rack directly via short lines (yellow). This then is electro-hydraulic or electric-over-hydraulic power steering, and it's the best of both worlds."

Last edited by GrantG; 06-10-2015 at 11:50 AM.
Old 05-11-2015, 09:43 PM
  #41  
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Check my last post on the previous page and here is an interview of McLaren principal by Chris Harris where they mention continuing to use this system in their new entry-level 570hp car (around 6:25 mark):
Old 05-11-2015, 10:40 PM
  #42  
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Very interesting indeed! TIL.
Old 05-12-2015, 10:44 PM
  #43  
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I don't understand comments about PSP being too light at parking speeds. I have driven several cars with variable assist and find the low speed effort in my Targa 4S to be significantly heavier than in other vehicles. In fact, I find the variable assist quite transparent. Until I read this thread, I completely forgot that I had the PSP. I find that it equalizes the steering heaviness across the speed range. No matter what speed you are traveling, a given amount of steering effort gives a predictable deflection of the steering wheel, at least until you really lean into a corner at speed, then the steering effort builds predictably to let you know that you are making it work.
Old 05-12-2015, 11:13 PM
  #44  
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Well, just because it is heavier than the "several cars with variable assist" you've driven doesn't mean it's not "too light at parking speeds."

To help those who can't understand those of us who have PSP and don't like it, let's just say it this way:

The Porsche PSP steering is a certain weight, let's call it "10." We like steering that is a heavier weight, let's call it "20." "10" is lighter than "20" by half, though it may very well be heavier than cars with steering weight of "5". Our older Porsches, as well as other sportscars we've owned, had steering that was in the "18" to "25" range, and we like that. Doesn't mean we think those of you who like your steering at "10" are bed wetters or limp-wristed wastrels with no redeeming qualities. In fact, we never think about you, in the context of steering or otherwise.

We simply like our steering to weigh "20."

Hope that helps promote understanding!
Old 05-13-2015, 12:24 AM
  #45  
thomnellie
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Originally Posted by NoGaBiker
Well, just because it is heavier than the "several cars with variable assist" you've driven doesn't mean it's not "too light at parking speeds."

To help those who can't understand those of us who have PSP and don't like it, let's just say it this way:

The Porsche PSP steering is a certain weight, let's call it "10." We like steering that is a heavier weight, let's call it "20." "10" is lighter than "20" by half, though it may very well be heavier than cars with steering weight of "5". Our older Porsches, as well as other sportscars we've owned, had steering that was in the "18" to "25" range, and we like that. Doesn't mean we think those of you who like your steering at "10" are bed wetters or limp-wristed wastrels with no redeeming qualities. In fact, we never think about you, in the context of steering or otherwise.

We simply like our steering to weigh "20."

Hope that helps promote understanding!
Sorry, didn't mean to offend.


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