Home » Public Forums » GMCnet » proportional power steering (is it possible for the GMC?)
|
|
| Re: [GMCnet] proportional power steering [message #200440 is a reply to message #200427] |
Sun, 03 March 2013 08:24   |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Kerry,
The very first photo in Don Wirth's PS paper at www.gmceast.com is of the
"torsion bar" which determines the amount of force required by the
steering. That would not give you speed dependent assist though. There
are also available variable ratio lead screws which might approximate that
effect. I thought I had such a box at one time, but it's moved on
somewhere. :-(
That's about the limit of my knowledge of the matter. When we recently
"rebuilt" that steering box, we did not remove, nor identify the location
of, that part. I do recall Don commenting once that NASCAR teams kept a
rack of them so they could quickly adapt to drivers' preferences and to
suit different tracks. Some research might reveal more information and
sources.
Ken H.
On Sun, Mar 3, 2013 at 6:35 AM, Kerry Pinkerton wrote:
>
> What I'd like is more assist in parking lots and less assist on the road
> at speed.
...
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: [GMCnet] proportional power steering [message #200444 is a reply to message #200440] |
Sun, 03 March 2013 09:03 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Kerry,
One more thought, Post Script: HER '87 Honda Prelude had speed-sensitive
steering. I never had any reason to find out how it worked, but I suspect
a transmission driven PS pressure regulator -- probably too integrated with
the rest of the drive train to be of any use to you, but perhaps worth
investigating.
Ken H.
On Sun, Mar 3, 2013 at 9:24 AM, Ken Henderson wrote:
> Kerry,
>
> The very first photo in Don Wirth's PS paper at www.gmceast.com is of the
> "torsion bar" which determines the amount of force required by the steering.
>
...
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: [GMCnet] proportional power steering [message #200451 is a reply to message #200427] |
Sun, 03 March 2013 10:11 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
Kerry, This is a possible explanation for your difficult steering effort at
slow speed. Is your ride height, particularly in the rear, too low? This
will alter caster, and if you have eccentric upper control arm bushings in
the rear of your upper control arms, the combination can and does make for
a lot of steering effort at low speeds on hard surfaces. But the plus side
of that combination is ROCK STEADY high speed steering with minimal imput.
Worth a check. If your caster is greater than 5 degrees, you might want to
back it down a degree and a half or so and try that.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On Mar 3, 2013 3:36 AM, "Kerry Pinkerton" <Pinkertonk@mchsi.com> wrote:
>
>
> During my recent power steering problem, I noticed as my fluid got low
> (and the pump was whining in the parking lot), that the highway speed
> steering was MUCH improved. MUCH It was not hard but you could actually
> feel the road.
>
> Now that I have repaired the leak (and needlessly replaced the PS
> pump...sigh :blush: ), I'm back to basically effortless steering on the
> road. One finger effortless. Reminds me of a mid 70's luxoboat...oh
> wait.... :twisted: 8o :lol:
>
> What I'd like is more assist in parking lots and less assist on the road
> at speed.
>
> I know Heidts makes an adjustable power steering valve.
>
> http://www.heidts.com/Scripts/default.asp
>
> Page 65 of their PDF manual. Apparently it works by restricting both the
> high pressure AND return lines. It is a manual valve so one would have to
> turn a knob to get more assist.
>
> I even thought about a thinner PS fluid perhaps reducing assist. My coach
> is super easy to turn even when parked. I would not object to having to put
> a little muscle into it. I'm not talking about 'Armstrong Power Steering'
> from the 50's (Power steering by your strong arm... 8o )
>
> Anyway, has anyone done anything like this or discussed this issue?
> --
> Kerry Pinkerton
>
> North Alabama, near Huntsville,
>
> 77 Eleganza II, "The Lady", 403CI, also a 76 Eleganza being re-bodied as
> an Art Deco car hauler
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
|
| Re: [GMCnet] proportional power steering [message #200455 is a reply to message #200427] |
Sun, 03 March 2013 10:24 |
Ronald Pottol
Messages: 505
Registered: September 2012
Location: Redwood City, California
Karma: -2
|
Senior Member |
|
|
Citron did it with a second pump on the transmission output to counter the
engine driven one, or so I heard.
Ron
On Mar 3, 2013 3:36 AM, "Kerry Pinkerton" <Pinkertonk@mchsi.com> wrote:
>
>
> During my recent power steering problem, I noticed as my fluid got low
> (and the pump was whining in the parking lot), that the highway speed
> steering was MUCH improved. MUCH It was not hard but you could actually
> feel the road.
>
> Now that I have repaired the leak (and needlessly replaced the PS
> pump...sigh :blush: ), I'm back to basically effortless steering on the
> road. One finger effortless. Reminds me of a mid 70's luxoboat...oh
> wait.... :twisted: 8o :lol:
>
> What I'd like is more assist in parking lots and less assist on the road
> at speed.
>
> I know Heidts makes an adjustable power steering valve.
>
> http://www.heidts.com/Scripts/default.asp
>
> Page 65 of their PDF manual. Apparently it works by restricting both the
> high pressure AND return lines. It is a manual valve so one would have to
> turn a knob to get more assist.
>
> I even thought about a thinner PS fluid perhaps reducing assist. My coach
> is super easy to turn even when parked. I would not object to having to put
> a little muscle into it. I'm not talking about 'Armstrong Power Steering'
> from the 50's (Power steering by your strong arm... 8o )
>
> Anyway, has anyone done anything like this or discussed this issue?
> --
> Kerry Pinkerton
>
> North Alabama, near Huntsville,
>
> 77 Eleganza II, "The Lady", 403CI, also a 76 Eleganza being re-bodied as
> an Art Deco car hauler
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
1973 26' GM outfitted
|
|
|
|
| Re: proportional power steering [message #200950 is a reply to message #200427] |
Thu, 07 March 2013 20:50 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
|
Senior Member |
|
|
""During my recent power steering problem, I noticed as my fluid got low (and the pump was whining in the parking lot), that the highway speed steering was MUCH improved. MUCH!!! It was not hard but you could actually feel the road.""
There are a dozen ways to get variable effort PS (intentionally that is) Most hydraulic systems will provide better road feedback when assist is reduced. Our system uses a torsion bar that controls the assist inside the gear. For years GM used magnasteer which was a hybrid electronic way to control effort. In the mid to late 90's, GM trucks used a variable orifice in the pump, but it was problematic. Electric power steering assist is finally maturing to the point where you can get totally variable effort without giving up steering feel. Next year, Nissan will be the first to pioneer steer by wire--are you ready ??
Bob de Kruyff
78 Eleganza
Chandler, AZ
|
|
|
|
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201042 is a reply to message #201005] |
Fri, 08 March 2013 17:18 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Keith,
Do you have a more specific application for the PWM variable orifice
valves? The existence of such a device, along with a PWM controller, could
make dash-potentiometer controllable steering effort trivially simple to
achieve. After implementing that with somthing like this:
http://www.apogeekits.com/pulse_width_modulator.htm it would be a
relatively small step to implement speed control of the PWM controller.
Ken H.
On Fri, Mar 8, 2013 at 1:10 PM, Keith V <my427v8@hotmail.com> wrote:
>
>
> Lots of GM cars, like saturns for example, have variable effort power
> steering that only really consist of a variable orifice valve in the back
> of the pump and something to control it.
>
> the factory way is PWM signal that varies with speed.
>
> I put the valve on my Vette when I put in a rack and pinion and control it
> with a switch.
> Hard steering, easy steering.
> easy steering in parking lots and rutted roads, firm steering when I want
> it :d
>
> The valve will screw into the back of the GMC pump, but you will need to
> change the PS hose fitting to screw into the valve
> --
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: proportional power steering [message #201060 is a reply to message #200427] |
Fri, 08 March 2013 20:14 |
Cadillackeeper
Messages: 464
Registered: October 2012
Location: Fort Lauderdale
Karma: 1
|
Senior Member |
|
|
Kerry,The coach does have what GM called variable ratio power steering.I f you turn fast the wheels will turn fast ,If you turn slow the wheels turn slow.The 67/8 Eldos were the first to have it.The rest of GM got it in 1970.You can tighten it.It is very sensitive.You loosen the outside nut and tighten the inside then tighten the outside.Kinda like an adjustable roller rocker
works.Have a pro help as it is unforgiving.Too far and its bad.....
77 455 Elaganza II and 67 Animal, Built 500 Powered Eldo
|
|
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201192 is a reply to message #201042] |
Sun, 10 March 2013 10:31 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
|
Senior Member |
|
|
| Ken Henderson wrote on Fri, 08 March 2013 17:18 |
Keith,
Do you have a more specific application for the PWM variable orifice
valves? The existence of such a device, along with a PWM controller, could
make dash-potentiometer controllable steering effort trivially simple to
achieve. After implementing that with somthing like this:
http://www.apogeekits.com/pulse_width_modulator.htm it would be a
relatively small step to implement speed control of the PWM controller.
|
Ken,
I don't have a full list, but Saturns definitely used them in the 90s I think Jeeps also used them, like cherokees etc
I think your link would work, but $21??
a simple 555 timer will do every bit as good for a dollar or two.
Like this
http://www.nomad.ee/micros/pwm555.html
Making it speed controlled would be cool.
Use a Frequency to voltage converter like this to drive the 555;
http://www.ti.com/lit/ds/snas555b/snas555b.pdf
tho a small pic micro could probably do it for under a dollar 
Thats my plan someday 
Heres a picture of one, small enough to fit in your pocket
http://www.gmcmhphotos.com/photos/data/6318/medium/SAM_0288.JPG
Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201200 is a reply to message #201192] |
Sun, 10 March 2013 12:13 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Keith,
I agree that there are cheaper ways to accomplish control of the pressure
regulator (though without knowing its characteristics I wouldn't jump to
the conclusion that a 555 can drive it). That first-cut suggestion of a
PWM kit was to give those with little electronics knowledge some concept of
how easily control could be implemented.
Sounds like you could easily create a control board and offer the rest of
us "Keith's Speed Variable Steering" kits. :-)
Ken H.
On Sun, Mar 10, 2013 at 11:31 AM, Keith V wrote:
>
>
> Ken Henderson wrote on Fri, 08 March 2013 17:18
> > Keith,
> >
> > Do you have a more specific application for the PWM variable orifice
> > valves? The existence of such a device, along with a PWM controller,
> could
> > make dash-potentiometer controllable steering effort trivially simple to
> > achieve. After implementing that with somthing like this:
> > http://www.apogeekits.com/pulse_width_modulator.htm it would be a
> > relatively small step to implement speed control of the PWM controller.
>
>
> Ken,
> I don't have a full list, but Saturns definitely used them in the 90s I
> think Jeeps also used them, like cherokees etc
> I think your link would work, but $21??
> a simple 555 timer will do every bit as good for a dollar or two.
> Like this
> http://www.nomad.ee/micros/pwm555.html
>
> Making it speed controlled would be cool.
> Use a Frequency to voltage converter like this to drive the 555;
> http://www.ti.com/lit/ds/snas555b/snas555b.pdf
>
> tho a small pic micro could probably do it for under a dollar :)
>
> Thats my plan someday ;)
>
> Heres a picture of one, small enough to fit in your pocket :)
> http://www.gmcmhphotos.com/photos/data/6318/medium/SAM_0288.JPG
> --
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201219 is a reply to message #201200] |
Sun, 10 March 2013 15:13 |
Surbo
Messages: 213
Registered: February 2004
Karma: 0
|
Senior Member |
|
|
| Ken Henderson wrote on Sun, 10 March 2013 12:13 |
Keith,
I agree that there are cheaper ways to accomplish control of the pressure
regulator (though without knowing its characteristics I wouldn't jump to
the conclusion that a 555 can drive it). That first-cut suggestion of a
PWM kit was to give those with little electronics knowledge some concept of
how easily control could be implemented.
Sounds like you could easily create a control board and offer the rest of
us "Keith's Speed Variable Steering" kits.
Ken H.
On Sun, Mar 10, 2013 at 11:31 AM, Keith V wrote:
>
>
> Ken Henderson wrote on Fri, 08 March 2013 17:18
> > Keith,
> >
> > Do you have a more specific application for the PWM variable orifice
> > valves? The existence of such a device, along with a PWM controller,
> could
> > make dash-potentiometer controllable steering effort trivially simple to
> > achieve. After implementing that with somthing like this:
> > http://www.apogeekits.com/pulse_width_modulator.htm it would be a
> > relatively small step to implement speed control of the PWM controller.
>
>
> Ken,
> I don't have a full list, but Saturns definitely used them in the 90s I
> think Jeeps also used them, like cherokees etc
> I think your link would work, but $21??
> a simple 555 timer will do every bit as good for a dollar or two.
> Like this
> http://www.nomad.ee/micros/pwm555.html
>
> Making it speed controlled would be cool.
> Use a Frequency to voltage converter like this to drive the 555;
> http://www.ti.com/lit/ds/snas555b/snas555b.pdf
>
> tho a small pic micro could probably do it for under a dollar
>
> Thats my plan someday
>
> Heres a picture of one, small enough to fit in your pocket
> http://www.gmcmhphotos.com/photos/data/6318/medium/SAM_0288.JPG
> --
>
Fella's;
GM tried using the EVO valve on the PS pump in the late 90's into the early 2000 vehicles. The idea was fine, but the results did not work out that way. A lot of steering twitch and loss of assist on curves, etc. GM has a conversion kit that will eliminate the EVO valve, which solves the problem. It made the Caddie Escalade group happy 
http://www.oehq.com/oeparts_19168825.htm
Here is some more info and pic's showing the EVO valve on a pump.
http://tinyurl.com/ag5tlmx
More info on the EVO valve;
http://my.cardone.com/techdocs/PT%2020-0024.pdf
Take care from Bob Drewes in SESD
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201238 is a reply to message #201219] |
Sun, 10 March 2013 18:42 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Thanks, Bob. As usual, you've come up with essential information that most
of us seem unable to locate. Was the EVO used on any heavy vehicles?
While the benefit might be greater on those than on light,
easy-to-steer-anyway cars, it seems to me that an EVO failure on a heavy
vehicle could lead to a much more serious situation.
With the 1-Ton front end, steering stability is good enough that I'm not
anxious to start experimenting with this, but it MIGHT be useful for those
with persistent problems.
Ken H.
On Sun, Mar 10, 2013 at 4:13 PM, Bob Drewes wrote:
>
> > GM tried using the EVO valve on the PS pump in the late 90's into the
> early 2000 vehicles. The idea was fine, but the results did not work out
> that way. A lot of steering twitch and loss of assist on curves, etc. GM
> has a conversion kit that will eliminate the EVO valve, which solves the
> problem. It made the Caddie Escalade group happy :lol:
> >
> > http://www.oehq.com/oeparts_19168825.htm
> >
> > Here is some more info and pic's showing the EVO valve on a pump.
> >
> > http://tinyurl.com/ag5tlmx
> >
> > More info on the EVO valve;
> >
> > http://my.cardone.com/techdocs/PT%2020-0024.pdf
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201256 is a reply to message #201238] |
Sun, 10 March 2013 22:09 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
|
Senior Member |
|
|
my wifes saturn has the valve and I like it, but as noted it's a light car, what 2500 lbs??
I also have one in the vette, it's problem is it has a rack and pinoin conversion that has too much assist. The valve allows me to adjust the assist as I want.
I never felt the GMC was over assisted, but I haven't driven it THAT much, just a 100 miles or so.
The valve can only increase effort when energiszd, it's failure mode is full assist
Lastly, I would not recommend making it speed sensitive, I would just give the driver control with a knob, so they can set it to however they liked it, that 555 circuit with a pot to adjust effort would be ideal. The valve only draws 1 amp max, so it's easy to drive
Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201291 is a reply to message #201256] |
Mon, 11 March 2013 09:54 |
Surbo
Messages: 213
Registered: February 2004
Karma: 0
|
Senior Member |
|
|
Howdy;
Here is some more details on the problems GM had with the control of the EVO valve in the late '90's to early 2000 vehicles. The ECM did the controlling of the orfice size at the output of the PS pump, the smaller the orifice size the less flow to the steering gearbox, which gave more road feel to the steering wheel. The inputs to the ECM were from the speed sensor (mph) and also from the steering angle sensor that was mounted on the bottom of the steering column. Depending what vehicle was involved, is what the speed and the angle of the steering angle sensor was programmed into the ECM to control the EVO valve. You can view the steering angle sensor at a NAPA website, do a search for ECH SWS123.
As soon as 70K miles, owners were complaing about erratic steering problems. GM said "you need an alingment" The result was no improvement. This included Escalade owners and into the 3500 series HD pickups. Some of the duallys pulling livestock trailers were even pulled over by smokies, because they thought by all the weaving that was going on, the driver was on to something!
GM tech's threw their hands up, offered the conversion kit #19168825, and let it go at that.
So, enter some DIY "farmers", with a tech tool, and looking at what is causing this problem. If GM would have just replaced the bearing at the lower steering column, it would have solved most, if not all, the twitchy steering problem. When you look at the steering angle sensor, you will see how critical the column shaft movement would be to the angle sensor and it's output to the ECM.
When this was told to the GM tech's, they either did not understand....or choose to turn a deaf ear.
And that, my friends, is a sad situation.
Bob Drewes in SESD
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201304 is a reply to message #201291] |
Mon, 11 March 2013 11:15 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Bob,
That's probably the first any of us here have heard of the steering angle
sensor. Its inclusion is, when you think about it, a logical decision, and
might even substitute, to a certain extent, for the speed sensor. The
plot's getting too thick for me, though! Especially when the angle sensor
is as critical as it proved to be. If I were tempted to try it, I'd
probably stick with a manual rheostat & on/off switch. By the time I
gathered enough empirical data from that to tempt me to get more
complicated, I'll be too old & CRS'd to go any further. :-)
You young wiz's carry on!
Ken H.
On Mon, Mar 11, 2013 at 10:55 AM, Bob Drewes wrote:
>
>
> Howdy;
>
> Here is some more details on the problems GM had with the control of the
> EVO valve in the late '90's to early 2000 vehicles. The ECM did the
> controlling of the orfice size at the output of the PS pump, the smaller
> the orifice size the less flow to the steering gearbox, which gave more
> road feel to the steering wheel. The inputs to the ECM were from the speed
> sensor (mph) and also from the steering angle sensor that was mounted on
> the bottom of the steering column. Depending what vehicle was involved, is
> what the speed and the angle of the steering angle sensor was programmed
> into the ECM to control the EVO valve. You can view the steering angle
> sensor at a NAPA website, do a search for ECH SWS123.
> As soon as 70K miles, owners were complaing about erratic steering
> problems. GM said "you need an alingment" The result was no improvement.
> This included Escalade owners and into the 3500 series HD pickups. Some of
> the duallys pulling livestock trailers were even pulled over by smokies,
> because they thought by all the weaving that was going on, the driver was
> on to something!
> GM tech's threw their hands up, offered the conversion kit #19168825, and
> let it go at that.
> So, enter some DIY "farmers", with a tech tool, and looking at what is
> causing this problem. If GM would have just replaced the bearing at the
> lower steering column, it would have solved most, if not all, the twitchy
> steering problem. When you look at the steering angle sensor, you will see
> how critical the column shaft movement would be to the angle sensor and
> it's output to the ECM.
> When this was told to the GM tech's, they either did not understand....or
> choose to turn a deaf ear.
> And that, my friends, is a sad situation.
>
> Bob Drewes in SESD
>
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201309 is a reply to message #201304] |
Mon, 11 March 2013 12:34 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
|
Senior Member |
|
|
Well, consider this. For those of us who haven't yet visited your Wiper Store, restircting the pump output may not be the absolutely smartest idea going. It'd be like our '47 Plymouth when I was a kid... the more you give it the gas, the less wipers yuo had. Or in this case, the faster you're going, the slower the wipers...
--johnbny
'76 23' transmode norris
'76 palm beach
________________________________
From: Ken Henderson <hend4800@bellsouth.net>
To: gmclist <gmclist@temp.gmcnet.org>
Sent: Monday, March 11, 2013 12:15 PM
Subject: Re: [GMCnet] proportional power steering
Bob,
That's probably the first any of us here have heard of the steering angle
sensor. Its inclusion is, when you think about it, a logical decision, and
might even substitute, to a certain extent, for the speed sensor. The
plot's getting too thick for me, though! Especially when the angle sensor
is as critical as it proved to be. If I were tempted to try it, I'd
probably stick with a manual rheostat & on/off switch. By the time I
gathered enough empirical data from that to tempt me to get more
complicated, I'll be too old & CRS'd to go any further. :-)
You young wiz's carry on!
Ken H.
On Mon, Mar 11, 2013 at 10:55 AM, Bob Drewes wrote:
>
>
> Howdy;
>
> Here is some more details on the problems GM had with the control of the
> EVO valve in the late '90's to early 2000 vehicles. The ECM did the
> controlling of the orfice size at the output of the PS pump, the smaller
> the orifice size the less flow to the steering gearbox, which gave more
> road feel to the steering wheel. The inputs to the ECM were from the speed
> sensor (mph) and also from the steering angle sensor that was mounted on
> the bottom of the steering column. Depending what vehicle was involved, is
> what the speed and the angle of the steering angle sensor was programmed
> into the ECM to control the EVO valve. You can view the steering angle
> sensor at a NAPA website, do a search for ECH SWS123.
> As soon as 70K miles, owners were complaing about erratic steering
> problems. GM said "you need an alingment" The result was no improvement.
> This included Escalade owners and into the 3500 series HD pickups. Some of
> the duallys pulling livestock trailers were even pulled over by smokies,
> because they thought by all the weaving that was going on, the driver was
> on to something!
> GM tech's threw their hands up, offered the conversion kit #19168825, and
> let it go at that.
> So, enter some DIY "farmers", with a tech tool, and looking at what is
> causing this problem. If GM would have just replaced the bearing at the
> lower steering column, it would have solved most, if not all, the twitchy
> steering problem. When you look at the steering angle sensor, you will see
> how critical the column shaft movement would be to the angle sensor and
> it's output to the ECM.
> When this was told to the GM tech's, they either did not understand....or
> choose to turn a deaf ear.
> And that, my friends, is a sad situation.
>
> Bob Drewes in SESD
>
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
|
|
|
|
| Re: [GMCnet] proportional power steering [message #201327 is a reply to message #201309] |
Mon, 11 March 2013 16:10 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Darn it, Johnny! Here I am trying to get everyone to restrict their
pressure so they'll want reliable, steady speed electric wipers & you go
let the cat out of the bag about my only slightly nefarious scheme!
Ken H.
On Mon, Mar 11, 2013 at 1:34 PM, Johnny Bridges wrote:
> Well, consider this. For those of us who haven't yet visited your Wiper
> Store, restircting the pump output may not be the absolutely smartest idea
> going. It'd be like our '47 Plymouth when I was a kid... the more you give
> it the gas, the less wipers yuo had. Or in this case, the faster you're
> going, the slower the wipers...
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
Goto Forum:
Current Time: Tue Nov 12 16:40:50 CST 2024
Total time taken to generate the page: 0.02286 seconds
|
GMCforum
Search
Help
Register
Login
Home
), I'm back to basically effortless steering on the road and even while parked. One finger effortless. Reminds me of a mid 70's luxoboat...oh wait.... 
