More on electric power steering conversion ...
 

I've reviewed a number of interesting threads here regarding electric power steering conversions. I'm looking for something SIMPLE that might work for my 1996 F-150, and this is what I'm thinking about:

Knowing when to run the pump and how hard seems to be a major issue with the OEM systems out there. I was considering a simple on / off operation when most needed, but don't want to use the manual switch method that has been discussed by others.

Since you only really need power steering during low speeds and parking, occurred to me that you might be able to wire a relay to the brake lights so that whenever you hit the brakes, you'd get power steering full on for xx (pick a number) seconds.

I also need recommendations for what would be an appropriate, well documented pump.

If you put it in gear while at low speed or parking the power steering pump will turn, it recently dawned on me that i can maintain my brakes and power steering by doing this.
I am thinking the guys from the EV world could be using something electric to power their steering pumps.

Not sure how automatics would perform with that technique, it may still work.

-here is a link about a hybrids, electric steering pump so they are out there.

http://ecomodder.com/forum/showthrea...wer-12558.html

If you choose XX seconds, you will inevitably have times when you're turning the wheel, XX elapses and the pump stops. Believe me, you will never like or get used to power assist cutting out in the middle of turning the wheel!


Speed-sensitive is better.

many newer cars have variable assist, at over xx mph the power steering is reduced or effectively disabled. this is how you want to do it, mostly you only need it when parking at 5mph or less, faster than that, it isn't needed,
and in fact the car handles better without it at speed.

knowing speed isn't hard, how to turn it on/off isn't so clear.
maybe a pulley clutch like an a/c is an option.
electric power steering is the simple way, but of course how to get
electric into the car is the question. prius has electric steering rack.

Not true for all cars ... though I would've said the same thing 2 weeks ago, I know now it's not the case!

My 2002 Hyundai Elantra is one of them, learned it the hard way, EOCing on the highway (downhill), then when I got to the curve at the bottom I realized turning the wheel needed both of my hands! It's not super hard but it's FAR from being easy.

I had an Elantra from the previous generation and it didn't much force to turn the steering wheel at highway speed, so it's something that changed in the generation that I now have!

sure, non-power steering isn't the same as disabled power steering!

yeah but like I said, the Elantra I had previously wasn't as bad as the one I have now. At highway speed, the older one was like I had the PS pump working, it was noticable but barely, this Elantra seems dangerous with the pump off!

Ever thought of trying to clutch your P/S pully?

Yes, but I have no idea about how to source the parts for this.

Is there a "how to" thread for this sort of thing?

Before I invest too much time and money into this I need to run some tests.
I plan on using a drill and a kill-a-watt meter to determin how much power it takes to idle my P/S pump.
Basicly connect a side drill to the P/S with the belt off, spin the drill up to its max RPM, record power consumption take an RPM reading.
Then operate the drill at the same RPM with no load and subtract that from loaded power consumption. Then record power consumption loaded and unloaded at 50% and 60%, 70%, 80% and 90% of full drill speed.
That way I can chart horse power consumption of my engine cruise speed of 1600rpms even if my drill only spins the pump to 1200 or 1000 rpms.

You would need to get a hydraulic pump clutch pully and adapt it from 1-1/4 keyed shaft to what ever your power steering pump is.
For me the process would be to source a 1-1/4 inch keyed shaft to .75'' press fit adaptor and wire it up.
My solution: http://www.hydraulicstore.com/clutchpumps.html
This clutch is way over kill for a 3.7gpm (standard GM saganaw flow rate) at less than 1000psi and should out last the pump its on.
What others have done:
http://ecomodder.com/forum/showthrea...ing-14952.html
Not sure how much punishment that clutch can take.

Another possibility might be to use a universal electric water pump drive kit.
Water Pump, Electric Drive Kits - SummitRacing.com
My consern there is that motor might not be strong enough to run a hydraulic pump.
And there is this:
Unisteer Performance 8051500 - Unisteer Electra Steer Kits - Overview - SummitRacing.com
Woefully under powered for a 6000lb suburban that tows.
Its not economical, that much money will buy a lota gas, unless you do it cause you dont have P/S and want it, but with out the drag that comes with running a pump all the time.

I thought about going to electric power steering, but my electrical system is already running hard enough, I have on board air compressor stuff to add, transmission cooler to move, new exhaust to run and water injection to expand.
Also hydraulic power gives me power braking, I dont have a vacuum brake booster.
So I need something small, dependable, didn't draw a ton of power so that pump clutch set up looks like what I need.

oil pan 4: Many thanks!

oil pan 4: I would never remove my thermactor / AIR pump for environmental reasons, but I've always wanted to know the power draw and whether there might be a smarter way to drive it. I've even thought about replacing it with an electric pump that could be more intelligently controlled.

Do you have one to test, or, if I sent you an air pump, could you run the same test on that?

The air pump does one of 2 things.
#1, does nothing more than provide proof the government approved solution to pollution is dilution.
#2, it may prevent back fires, but on a properly maintained vehicle its not likely any way.

The air pump is just another accessory to turn, it doesn't do anything besides use more fuel. It makes emissions look cleaner by cheating, it blows air onto the exhaust, you would get the same effect by holding the emissions probe several inches away from the exhaust out let. Thats all its doing. It adds air to the exhaust to get tail pipe NOx down, even tho the vehicle produces the same amount of NOx with or with out it.

Aren't there any Mazda electric racks at the wreckers, yet? If I recall, some Mazdas had electric hydraulic pumps... which might or might not work for you.

"Sportier" steering rack (shorter ratio). Harder to turn with assist off.

now I know this may or may not help you but.

I have a honda element and I just did a EPS swap I used a EPS rack from a 02-04 civic si.

when it came down to it the system is very simple. all together the whole setup consisted of 15 wires. a rack. a motor mounted to the rack and a small ecu

but in the end most was for diag or dash lights.

it consisted of 60A fused 4 gauge power,4 gauge ground. and wires getting signals from IGN(keyed power),VSS(vehicle speed),ESS(rpm)

not that it would help a large vehicle(though it may) the system is very compact and getting standalone sensors would not be hard

http://i75.photobucket.com/albums/i3...ll/EPSrack.jpg

I'd be only concerned about the reliability of a light-duty EPS rack into a heavier vehicle...


The so-called "progressive power steering" is a very usual feature in other countries, but since Murricans enjoy those setups which can have the steering wheel turned with only one finger it's not so usual in the U.S. as in Europe.