MR2 Spyder Electric Power Steering conversion

[Bob H]

I was putting this up for sale, but wanted to capture the info for others who were looking to do something like this so I'm putting up this thread as well. 
 I had this installed in this car:


Build thread here to show you how detailed oriented I am:

http://www.norotors.com/index.php?topic=348.50
In post #16 I referenced my plan to install it.  Never finished documenting the install so I'll do that below.
 
 In short, Zdan bought the car, didn't like the setup and may have been having some issues with it performing as intended, so he pulled it and installed a regular GM G8 PS Pump and gave me the old setup since I had so much time and $$$ invested in the setup. 

What is this?
In short, MR2 Spyder,('00-05) electric power steering pump, mounts are modified to fit into a custom aluminum mount that I bolted to the FD framerail up front.  I fabricated the mount to work with a Samberg Radiator and the available space.  I also had a a custom speed controller that when installed, can create a decreasing assistance with increasing speed or any custom profile, (i.e. high assist for parking lots, lower assist for high speed). I never got the chance to hook up the controller as I was working out the hydraulic and mounting/wiring issues first.  I bring this up early as I think this controller is a good idea regardless of your setup. 

OK, Why the MR2 Spyder pump and not the older MR2 pump?  In short, the 00-05 MR2 Spyder PS pump has an integrated controller and reservoir.  That plus newer = more likely to be in good shape! 

Before I put the pics, I used this as a go-by when I was wiring/learning what is needed:
http://www.k20a.org/forum/showthread.php?t=58599

I used a spare relay wiring from the FD that was left-over after the LS swap.  I think I utilized the Air Pump relay, but I don't recall.  Bottom line - one that wasn't utilized after the swap and I was using the ABS, AC, etc..   Strong consideration may be given to wiring in an entirely separate circuit using something like mentioned in the thread linked above - i.e. using a Honda Relay/power setup.     
 Some "questions" are answered at the bottom.  If those don't answer what you want to know - just post and ask. 
 Unfortunately, I don't have any pics when it was installed in the FD.  I'm sure I took some, I just can't find them right now.  Maybe whoever buys it will post some up. 

Ok, here are pics/info:



Close-up of where I cut and re-welded the mounting arm:



Clean Reservoir:



Bracket I made to go on the FD frame rail.  The "cutout" is for a raised section on the FD rail that interfered with it laying flat against the rail.  Should be obvious when you look at your car on the frame rail on the drivers side near the front:



Underside shot of bracket showing how I ground it all flat/etc..  You can see the "cutout" better in this pic:



Shot of it mounted to the bracket:



Angle showing clearance for the PS pressure output:



Some PS fittings - showing my custom one to make the turn near the fender.  You can order ones that would clear, it was cheaper for me to make one while I was still experimenting with routing/placement/etc..  NO we don't have those anymore - they were used with the replacement setup.  The two I'm pointing to are for the pump output and the rack input.  Pump output is my "modified" one.  The others are just fittings I had for other projects.  Missing from the rightmost fitting is the small o-ring it needs for installation:



Wires already cleaned up and ready to go!:



I'm pretty sure I had to install at least one nutsert in a hole in the framerail, maybe 2.  These are nutserts for reference:




Ok, supplement to the original post to answer questions I think people would have if looking to do this:

Why do this?
-Because racecar. 
No really...     Ok, because I wanted high assist in the parking lot, low assist on the track.  Not possible with a GM power steering pump or any belt driven setup.  G8 and GTO pump were pretty good - but I was looking for better.  Plus its cool.  Less HP robbed of course! 

What do I have to do to install this?
-Put yourself in the cool club if not already a member.  Oh, you mean to install it! 
First, you must source a MR2 Spyder pump and I suggest reaching out to the guy who made the controller I reference later in this post to get that as well. 
 Second, you have to figure out where you can mount it.  I didn't want that third mounting point WAAAY out in the center of the space between the radiator and the pulleys, so I cut and changed its position.  You must also consider the Pressure output and return to reservoir location.  The return is FIXED and can't be rotated.  Trust me, I tried.  The orientation I did was dictated by the fact that I wanted to cut/reposition the "long" mounting ear, so that tied my hands for the rest.   
Third, you must figure out the wiring and power.  This can pull up to 30 amps.  Unlikely, but you must wire it for such in the event you have the wheel at full lock and push further, (that is the highest/peak pressure typically). 
 Fourth, don't forget when buying hose - buy hose SPECIFICALLY designed for Power Steering systems.  Don't learn the hard way like I did with my GTO pump in my first conversion.... 
 For the return, I suggest something like this:
http://www.amazon.com/Edelmann-71350-Power-Steering-Return/dp/B000CGROW4
 That is for the GM trucks, but the hose is rated for the high temp and composition of the PS fluid.  Plus it comes with a cool small filter,(for big metal parts mainly). 

If you need to ask what must happen after those items above - you likely shouldn't tackle this.  In short, create your custom mount, (you can consider asking the guy in the very first link from K20a forum for one of his mounts - not sure if they would work), sort out the wiring, sort out the hydraulic lines, hook up the speed wire or the controller,(my suggestion over just a speed wire), and then have fun!
 
Will this work with my pulley setup?

FOR THE FDs: I had the G8/GTO depth pulleys and the Samberg radiator.  I tried to find a pic of it installed, but I can't.  So if you have the Samberg setup and the F-body depth pulleys...  I make no promises as there may not be enough room.  I seem to remember I had good clearance, but I can't find a pic, so you take your chances if that is your setup....  If you have a vertical radiator setup with anything other than the Truck depth pulleys, you should be fine but may have to move the mounting point forward from where I mounted it. 

FOR THE FCs:  I think you have a lot more room - shouldn't be an issue but check yourself. 

Tell me more about this speed controller and where is it in the pics?
 It is in the first pic - to the far right of the parts pictured.  It is a small circuit board.  It was made up by a guy named Ian building a GTM and I bought one of the last ones he made, (He may still do them, but that was back in 2009)  I have a document that has instructions on how to wire it up and how to change the settings and even how to hook up a pot, (an ability to just move a dial to change assist).  In short, you put a power and ground, and intercept the speed wire as appropriate per the instructions.   I would HIGHLY RECOMMEND that if you are doing this conversion, you utilize this controller.  Why keep the pump at a constant speed all the time?  Defeats the purpose/benefit of having an electronic PS! 
 
 Guy who made it posted here.  Post #29 is who made the boards,(Ian) and explains several things.  Post #53 is someone who installed it and describes the benefits of changing the settings.  Those are the two posts I'd read in the entire thread linked below.    You can use his controller with non MR2 Spyder pumps - he outlines that in his post 29 to an extent and in his instructions.  Cost is $50, or rather in 2009 it was $50.  Email and ask him.  His name is Ian. 
http://www.ffcars.com/forums/42-factory-five-gtm-forum/208188-power-steering-pump-controller-installed-working.html

And how he installed it in his car:



Any other questions - just post and I'll do my best to answer! 

[freeskier7791]

Very cool setup, Have you ever come along metric inverted flare to AN fittings?  My Fragola straight 14mm to -6AN is leaking

[Bowtie7]

Gotta wonder if the added electrical load on the alternator = parasitic loss of belt driven pump. For the same reason I wont use electric waterpump, if the motor fails or faulty circuit you end up on side of track/road watching everyone go by. Big fan of simplicity and steering feel on Dan's car is spot on. Personally, I've run TurnOne/Fbody and GTO pumps back to back and noticed no difference in feel. The GTO pump runs hotter than Fbody so I swapped back to Fbody and I like the look better as well

[scuter83]

Look at all the OEM's going to EPAS.  Gotta think the benefit is fuel economy especially with the smarter alternator control now.  Some driveability with power steering cramp at low speed as well.

[Bowtie7]

Look at all the OEM's going to EPAS.  Gotta think the benefit is fuel economy especially with the smarter alternator control now.  Some driveability with power steering cramp at low speed as well.

Agreed, difference being totally designed around it.

[digitalsolo]

Like Charlie noted, EPAS will be WAY more efficient than an electric pump slinging fluid to an old school rack.    Pumps are inefficient things.

[Bob H]

Very cool setup, Have you ever come along metric inverted flare to AN fittings?  My Fragola straight 14mm to -6AN is leaking

Yes, in that picture - the blue AN fitting.  They are out there - you just have to find it in the various catalogs of summit, etc.. 

I did this originally for two reasons.  The background was I had a F-body PS pump on my first LS swapped FD which I changed out for a GTO pump.  I have a big thread on ls1tech.com with all the outputs/pressures of the various GM PS pumps.  If I recall correctly, the F-body was a higher flow rate, slightly higher pressure vs. the GTO.  The GTO pump was very close to the stock FD PS pump output in pressure and volume.   It required some creativity in mounting the reservoir, but not insurmountable considering you are swapping a domestic V8 into a foreign rotary car.  I personally found the GTO pump, (and by extension, the G8 pump which Dan now has on his car), to be an outstanding match for the FD for feel.  How the GTO achieves that lower flow and pressure might be why Charlie found it to run hotter.  The Turn 1 pump does lower the pressure, which has a secondary impact of also lowering the flow but via a restriction, which can heat the fluid up more.  Sounds like the Turn 1 did run cooler - which is a positive in my book if the feel is correct.  I absolutely DID NOT like the F-body pump feel at speed - overboosted.  A personal opinion, but part of the reason I switched to the GTO and eventually to this electric setup so I could tweak it to my personal liking. 
 I realized I would gain some power by not turning the hydraulic PS pump at all since it would be removed, and would be working the alternator slightly harder, I felt the net should be slightly positive.  I came to this position because my belief that the HP load from the alternator to create an extra 20 amps extra was most likely lower than the HP required to turn the PS pump at 5000 rpm while providing pressure for turning the steering rack.  No actual data, just my opinion and how I helped justify spending over $500 and all this time creating this setup.  However, freeing up hp was not my main goal.  My main objective was to minimize overheating of the PS fluid on the track where I would be running 4-7k rpm for the entire sessions.  If I could at least match the capability of a belt driven pump, but turn that pump, (electric in this case), at a lower pressure and volume, I would reduce the impact of high rpm increasing the PS fluid temp as it did in a belt driven setup. 

 Unlike the waterpump, PS pressure and volume required is not a function of RPM but rather speed.  Where the need for more coolant flow/volume is highest at the max RPM/loads, PS pressure/output requires are dictated by speed,(lower = more force needed, higher speed = lower needed depending on personal preference).  This is a primary reason electric water pumps for the LS motors are inadequate for extended high rpm/load conditions.   

 This PS pump, (MR2 spyder) is also better option vs. the early MR2 PS pump as it varies output based on speed even without the custom controller I had.  This meant it doesn't run at full tilt all the time, only when predominately needed, (slow speed) or if you program it through the custom controller to run at full pressure all the time,(if you don't input a speed wire, I believe it defaults to the max programed available pressure and during my testing you could hear the pump spin up to a higher speed when the speed input was nothing,(similar to stopped), and the pump motor slowed progressively as the speed was raised,(i.e. it saw the speed input wire).
 
 Why do it?  The main reason in my opinion is complete control over the assist at a number of different speeds -not possible with a belt driven pump and you are stuck with the pre-programed curve if you utilize the stock PS pump controller.  The secondary reason is heat in the PS fluid.  In my experience and opinion, without a PS cooler up front, you WILL overheat in a hot track environment and your choice of PS pump will impact this as well.    Last reason would be because you want something slightly different and are seeking absolute maximum HP output by minimizing any parasitic drag, (such as the hydraulic PS pump).  We are talking a few HP at best here, so keep a reasonable outlook on the gains if any.     
 I agree that a EPAS would be more efficient, but I found the electrical load of this pump to be very manageable, (ran about 5-15 amps once running, peaked output well over 20 amps at full lock but you don't often go to full lock and continue pressure except at parking lot speeds. 

[MPbdy]

I have the GTO pull and wouldn't change a thing about the steering on my fd except I want a faster steering rack. I have gotten fluid spraying out of it a couple times in canyons and autox. It hits the pulley somehow because it throws that shit everywhere.

I have an early turbo mr2 pump somewhere in my garage if someone wants it. Bought it when zdan originally posted about it way back in the day. Power steering feel used to be a much more common discussion before turn 1 and other pump options became available.

[Bob H]

.. I have gotten fluid spraying out of it a couple times in canyons and autox. It hits the pulley somehow because it throws that shit everywhere.
...

Agree 100% on the faster rack - would love that.  For your spraying out - sounds very much like overheating.  Consider at least a PS cooler up front if you don't already have one.  If you do - maybe a better designed one?