Sweet power steering servo?

[mrn2obelvedere]

What exactly does one of these do?

http://www.speedwaymotors.com/Sweet-Mfg-Power-Steering-Servos,1963.html

Is this what gives the "power" in power steering? Could I place this in tandem with my manual steering box for a kind of light weight hybrid power steering setup?

[David Pozzi]

A servo has a hydraulic motor inside, it boosts steering power like power steering but uses your manual box. I put one on a forklift we use on our farm, it looked similar. A lot of torque goes through the output shaft so it needs to be connected to the box properly. This unit does not speed up a slow box however and I can't say it would have all that great a feel to it. I don't think it would save weight at all, and it needs room to be fit between the box and steering column so would only work on a front steer car.

A similar looking unit is used as a control valve on a rack, but the valve controls an external slave cylinder, or in other terms, a hydraulic ram. The valve is a bit smaller and has 4 hyd lines.

https://static1.pt-content.com/images/noimg.gif

[mrn2obelvedere]

Well the advertised weight of this part is something like 5 pounds. My car is a Plymouth and the only factory based options are a very heavy power steering box, a fairly lightweight aluminum manual box, or the flaming river manual box which is made of steel. I think this servo in combination with my lightweight manual box would be significantly lighter than the PS box.

[monteboy84]

Have you considered using an electric power steering unit from a late-model vehicle?

The GM units use fairly simple wiring basically a power wire and speed input, I plan to rig one up under the dash of my Monte. The GM factory unit is very similar to this unit from Flaming River:
http://www.rodandcustommagazine.com/techarticles/0804rc_flaming_rivers_electronic_steering_system/index.html
https://static1.pt-content.com/images/pt/2010/01/0804rc_02_zflaming_rivers_electronic_ste-1.jpg

[mrn2obelvedere]

I'm really not into the idea of chopping up the K frame on the front to try to adapt a different steering box. I can fabricate brackets to adapt parts and even weld stuff as long as it is relatively simple, but completely re working the steering box mounting is a bit beyond my current means.

[monteboy84]

Oh no, the electric unit just goes inline with your steering shaft, same as the servo mentioned earlier. Typically they're mounted as part of the steering column up under the dash.

Either way, no biggie, just throwing it out there since you seem to be in the concept stage.