Electric power steering.

[jbennett58]

I have been wanting to add electric power steering to my s13.Does anybody have any experiance with retrofittng some of any EPS systems.

[PerilousActs]

The MR2 system is pretty popular and can be had for fairly cheap.

[Def]

Is there any way to change the amount of steering assist with these? Just vary the voltage or current to the pump? Or does it need a separate PWM or voltage signal or something like that?

[eazye2000]

I can get some measurements off our '09 Versa and see if it comes close to fitting for sake of ease.
But I have no idea what all you need to make that stuff work...

[PerilousActs]

Is there any way to change the amount of steering assist with these? Just vary the voltage or current to the pump? Or does it need a separate PWM or voltage signal or something like that?

Yes, you can have full control over this setup, if you want to run it through a controller. I've done some research on it for my daily. It's bagged and my axle rubs my power steering pump pulley when I ride low, so the current pump has gotta go.

http://evdrive.com/BMW_project/PowerSteering.html

http://www.driveev.com/jeepev/convpgs/psteer.php

" As a last note, the MR2 Power steering pump has an extra four-wire wiring harness coming out of it. This harness originally connected to a computer on the MR2 which varied the speed (through Pulse Width Modulation) of the pump in relation to the vehicle speed. This makes sense because the pump really never needs to run at full speed while the vehicle is moving since once the tires are rolling, less force is required to steer. At this time I haven't connected these wires to anything, but in the future I plan to make a PWM controller circuit for the pump. "

http://www.cameronsoftware.com/ev/EV_PowerSteering_Install.html

http://www.diyelectriccar.com/forums/showthread.php?t=19505

There's a lot more info out there on these, but those are the ones I have bookmarked and handy. The setup from the current gen MR2 seems to be the most compact and is the one I planned on using.

[logr]

I have seen the new Mini pump used with great success. One local builder has installed a few and seems to like it best. I have considered doing it but have doubts about it working very well with my small battery.

[CodyAce]

I have seen the new Mini pump used with great success. One local builder has installed a few and seems to like it best. I have considered doing it but have doubts about it working very well with my small battery.

Battery size shouldn't have any effect on how it works...that's your alternators job. (I make bolt on 115/125 amp Quest Conversion kits for sr20 if you're intersted, send me a pm )

[KA240SX808]

Some info I've gathered over the past couple months researching this:

92-95 MR2 EHPS
Draws over 75+A at times

00-05 MR2
Requires only 50A Fuse & Relay
Draws 4A @ Idle
Draws 40A @ Full Load



It does has a VSS Input but I'm not sure on the PPM count for the 00-05 MR2. It can be left un-signaled and is said to wind down slowly on it's own. With the VSS Signal it'll react faster to winding down and such.

Note: VSS Signal is not requires for the Pump to run.

[Mr. J]

I have been wanting to add electric power steering to my s13.Does anybody have any experiance with retrofittng some of any EPS systems.

Are you talking about electric power steering or an electric power steering pump?

Here is a thread discussing EPS: http://nissanroadracing.com/showthre...power+steering

[KA240SX808]

I believe he was talking about EHPS as it would be much easier to adapt that to our already Hydraulic system then to hack and steering column to add a EPS.

[PerilousActs]

The above is the MR2 pump. They have their own controlling computer.

[kingkilburn]

From what I've found you need the pump, power steering computer, sensor for the steering wheel, and the proper signal for the mph of the car.

I'm very eager to see how well the system works in an S chassis cause I wont have room for a conventional pump with what I'm planning and I'd rather not drop ps all together.

[PerilousActs]

You don't want to rig it up that way. The ECU adjusts the amount of steering adjustment when you turn the wheel based upon how fast you are going. So predictability goes out the window. You're better off wiring it to a high/low switch circuit.

[kingkilburn]

I think you are better off using the system as designed with the standalone power steering computer deciding how much pressure is needed with the speed the vehicle is going.

[Def]

Would it be bad to just have the steering assist drop off as the speed increased? Maybe reaching minimum assist by the time you get around 40-50 mph.

Actually, our cars aren't that horrible without power steering, so as long as you had some "minimal assist" it'd probably be fine and feel pretty good.

Or would that not work at all?