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What's the difference between the two and is one considered better than the other?
 

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The variable assist reduces the assist at higher speeds, so the steering feels heavier. I normally unplug the sensor at the steering shaft, so I have full assist all the time.
 

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If you do not have the variable assist as OEM, you may not be able to install it.
 

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The variable assist reduces the assist at higher speeds, so the steering feels heavier. I normally unplug the sensor at the steering shaft, so I have full assist all the time.
Cory, what is it that you don't like about the increased effort condition?

NV7 (only installed on Roadmaster & Fleetwood) has the following components:

- Specific variable rate steering gear 16:1 at center, 13:1 at lock
- PS pump with flow control (EVO = electronic variable output)
- Steering column sensor (potentiometer) - rate of rotation, angle off of center affect signal to flow control--on center & no steering shaft rotation provides greatest reduction of pump output (not sure of vehicle speed input or impact)
- Process controller to regulate pump flow control based on above inputs
- Specific pressure line from pump to gear
- Wiring harness and connector to power source to run controller & flow valve

The steering damper was standard on both Buick & Cad in 1993 as a result of problems in 1992 Roadmaster with customer complaints about vague on-center feeling--a TSB was issued to backfit early NV7 cars with the steering damper as the "fix".


If you do not have the variable assist as OEM, you may not be able to install it.
Fred, it's alot of stuff to change, but certainly COULD be incorporated on a car built without it....
 

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I believe D-Lo's question is related to his other thread where it appears he's getting cloverleaf jerkover.

Bill, there's talk on that thread about the valve in PS pump. Do you know if that's an easily serviceable-replaceable item? I've personally never heard a positive fix for the mystery twitches that FWBs (and apparently Roadmasters) suffer from. You either live with it, or unplug the firewall connector as Cory mentions.
 

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Bob, I want to think the simpler approach is to unplug the connector at the flow control on the PS pump--but I suppose disabling any part of the system "kills" it's functionality.

What I don't know is what happens by doing what you stated...I'm reasonably certain the pump goes to a default "full flow" condition if the flow valve is disconnected. I do wonder whether leaving the flow valve connected (and instead disabling the system by another method) possibly allows it to "drift", meaning assist level may not be consistent--but that sounds like the problem some seem to experience anyway.
 
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