PS pump orifice....
Thread Starter
Racer
Joined: Sep 2005
Posts: 330
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From: Lurkerville
PS pump orifice....
I have a Steeroid rack installed and the steering feels too easy (little effort) to turn from that of stock. I remember reading long ago that someone installed an orifice to make the turning feel more like stock.........but damned if I can find the post again.
Ring a bell to anyone???
Ring a bell to anyone???
Le Mans Master
Joined: Jul 2000
Posts: 6,001
Likes: 112
From: Saginaw Michigan
Reducing the flow from the pump will have a minor affect on the effort and feel. The problem is that by the time that you reduce the flow sufficient to make a decent change in effort, you probably will not be able to make a quick steering maneuver. What you will find is that the effort will suddenly increase (higher than just manual effort) if you try to whip the steering wheel as if making an evasive maneuver.
The best fix is to replace the gear with one that has a higher effort valve. I would contact Steeroids and indicate your dissatisfaction. Their supplier for the rack and pinion gear should have better control as to what they rebuild and ship.
Jim
The best fix is to replace the gear with one that has a higher effort valve. I would contact Steeroids and indicate your dissatisfaction. Their supplier for the rack and pinion gear should have better control as to what they rebuild and ship.
Jim
Le Mans Master
Joined: Nov 2003
Posts: 5,771
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From: Maryland
St. Jude Donor '05, '09, '15
I had the same too much assist feeling in my 65 when I added the Steeroids set up. I called them and bought a kit for the flow control valve. I used all the supplied shims. Still still a bit too much assist but it did help. It was worth the 25 bucks. 
The kit shows a later pump but works on earlier style pumps as well.
PS Flow Control.PDF
The kit shows a later pump but works on earlier style pumps as well.
PS Flow Control.PDF
Le Mans Master
Joined: Nov 2003
Posts: 5,771
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
Le Mans Master
Joined: Jul 2000
Posts: 6,001
Likes: 112
From: Saginaw Michigan
Those shims set the ultimate pressure that the pump can develop. That is known as the pressure relief setting. Only at full lock or when steering with the car stopped and nearing full lock do you ever crack the pressure relief valve. That setting should have no affect on down the road steering effort and feel.
Jim
Jim
Le Mans Master
Joined: Nov 2003
Posts: 5,771
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
Those shims set the ultimate pressure that the pump can develop. That is known as the pressure relief setting. Only at full lock or when steering with the car stopped and nearing full lock do you ever crack the pressure relief valve. That setting should have no affect on down the road steering effort and feel.
Jim
Jim
Le Mans Master
Joined: Jul 2000
Posts: 6,001
Likes: 112
From: Saginaw Michigan
Interesting. It sure feels like the assist was reduced. According to the chart that came with the kit installing all the all the shims drops the pressure from 1350 to 700 lbs. I don't know what the actual pressure was before I started or what it is now. If the operating pressure was above the 700 lbs seems like it would bleed it off even if you were not at full lock? Yes...No....Maybe? Any idea what the normal operating pressure is at say 1500 rpm?
Jim
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Le Mans Master
Joined: Nov 2003
Posts: 5,771
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From: Maryland
St. Jude Donor '05, '09, '15
Driving straight down the road your power assist pressure is probably only 50 to 100 psi when making minor lane changes. You will not be even close to the 700 psi pressure relief setting. I don't have an explanation as to why your steering would feel better with the shims installed under the hex nut.
Jim
Jim
Hmmmmmmmm.
Now you've got me wondering. I shimmed the valve a while ago. At the time it sure felt like the assist was reduced. This will drive me nuts now.
I may have to find a pressure gauge and check it.
