Jump to content

Subaru Power Steering


620Z

Recommended Posts

Hi I have been doing a lot of reading on these steering racks and it looks like the way to go for a conversion in the Zed. My question here is does anyone know if these racks when in the normal Subaru are totally manual? Or are they linked to an electronic device to soften the steering when you reach higher speeds? Some people say they or any power steering gets a little twitchy at high speeds but I don't know if they have dampners (for the want of a better word) to prevent this at high speeds?

At this point I am thinking they are totally manual and that the only way to regulate the above problem would be playing around with Pulley sizes to vary the speed of the oil pump. What that does at low speed I have no idea.

Hopefully some one here can shed some light on this since I am about to undertake the conversion in the next few months. I thought of contacting Subaru but figured I probably wouldn't be able to find anyone who would be interested in giving me any info since it would be going into a different car.

Craig

Link to comment
Share on other sites

Craig ill say they are manual. mine came of a subaru liberty/leone and i have checked these cars in person. no electronic attachement in the power steer system to  adjust the dampening. just a regular power steering pump. but i do know some cars seem to stiffen the power steering when traveling at higher speeds. maybe its mechanicaly compensated in the pump at higher revs. who knows. i know on my s14 steering get quite heavy at higher speeds. again no sensors or any electrical connections on the rack or the pump.

 

cant say too much about twichiness so far ive only been up to 130km for very short period. for that time I didnt feel anything wierd. though when im on certain roads (truck destroyed ones) car seem to be tracking the road and kinda have to wrestle with it to keep where i want to go. also my tyres are fairly shody so im putting it at that for the time being till i get better tyres as it seems to be doing this only in industrial areas where theres lot of trucks. other roads seems good.

 

i know that the skylines have a pressure switch inline with high pressure line to bump the idle up on the engine when car is being parked at (which i havent wired in yet LOL slack but engine seems to handle it well)

 

i was aksed previously about what power steer pump i used and its pressure ./and that person did say that r32 skyline ones / RB30 skyline and VL have similar pressure as the subaru one and that it will be suitable pump for the rack.  so far i cant complain.

 

 

Link to comment
Share on other sites

Thanks for the info RBZ260 that is the info I was after. Obviously I am a little worried about the damping since the car will be on the track and doing around 240klms so I am not sure what will happen at those speeds. Although I have found a Power Steering Flow Valve on a US site that seems to work as a bit of a Dampner. I have kept a copy of the write up just in case there is a problem. By the way is sounds like that wandering of your car might be a Bump Steer issue. I used to have the same problem. When I swap the racks over I will have to revisit and align things to ensure it doesn't start again.

Scott I think the MX5 might be an easier swap over because of the diametre of the rack. But I haven't seen much written up on them and was thinking the Subi Rack might have a lighter feel to it with my weight. Since I don't want to be doing this twice I will go with the tried and tested or proven results.

My biggest problem will be the rack hitting my harmonic balancer. At the moment it is only about 3mm between the two. But the Subi Rack will hit it so I have to go a smaller diametre balancer and or move the balancer forward 10-20mm to miss it. All this will be worked out in the next few months.

Link to comment
Share on other sites

write up? ill prob confuse ppl more LOL.

yeah could do with one but i think ive done it on the other forum. ill try and dig it out and link it up. also has some pics on there too.

 

Craig yeah that wondering is annoying thoug like i said only happends on certain roads. i remember my s14 used to do the same thing till i changed new tyres and got it re aligned it gone away. though the z has been wheel aligned 3 month ago and i havent collected any gutters yet.

 

as for the rack yeah i did the same thing went for done and proven concept. as i tried using an rx7 one (as i had it lying around) and was total waste of time. found a rebuild subi rack got the power head rotated and new pipes made.

 

ive cut and shut the rest of the hoses and pipes between subaru attachements and skyline ones.

though probably going to enzed with the right ends and dimensions would have been better but this way was cheaper for me. as i wanted to have that idle bump switch in the line and enzed werent that helpfull doing complicated things. they are more interested in give ends and lenght of the hose and we do the rest.

 

as for the engine mounts on the v8 craig are you using the stock L series subframe brackets or you have fabricated new ones of the chassis rails?

Link to comment
Share on other sites

http://www.thezgarage.com/forum/viewtopic.php?t=601&highlight=power+steering

 

there was another post with a yellow 240 with subaru rack but its pretty much like the first one the link above.

 

you can see what ive done on my replies to original post. LOL Craig you have replied to that post too.

 

i guess this was more of a info to SCO_AUS what is involved with such conversion.

 

 

Link to comment
Share on other sites

Yeah my engine mount is like a boat mount.  Metal bracket that goes around the front of the motor and wraps around the sides to the original mounts. This leaves heaps of room for the extractors and shouldn't be in the way for the conversions. Maybe a smal nick on one side but that would be it.

Are you able to tell me more about the idle Bump Switch? Do you have that working and how was it rigged up?

If you are still having steering issues I would get the bump steer looked at next time it's getting an alignment.

Link to comment
Share on other sites

idle bump switch

 

these things are located in the pressure side of the steering rack. its basicaly a switch when pressurised it closes or opens  and that is fed to the ecu input.Than the  ecu adjust the idle slightly higher.

 

i guess u can do that to yours to but being carby and all not sure what u can do to tell it to idle higher. than again being a v8 im sure its got plenty of torque and power on idle to run a small power steer pump.

 

i need to extend the wires to the loom to wire this thing up. im asuming that when switch is open it tells the ecu to run bit faster idle. as currently my idle wont go bellow 950rpm. should be 800.  but too slack and busy to wire it up and check it out.

im  more interested in squizing more power out of it at the moment LOL.

 

to test it while car is stationary just slightly turn the steering wheel and u notice a bump in idle from ie 800rpm to 1000rpm. similar thing happens also with airconditioner. it bumps the idle up when a/c is switched on to maintain correct idle speed but thats a seperate switch and seperate input.

 

as for the bump steer i though having power steer in eliminates it? what adjustments has to be made to get rid of it. ie toe in, camber,castor? i was thinking its doing that wondering because of crappy worn tyres.

 

ill try and wire that PS switch up tonight and let you know how it works.

 

 

 

 

Link to comment
Share on other sites

CHANGE THE tie rod to lower cont arm angle through bump travel. ie bump steer, as it bumps it wants to steer or 'wander'

 

lower the lca pickup @ the strut or lift the rack postion a lil, try to maintain parallel between the 2 arms, however some bump steer is desirable, but  not the whole hog Z bump steer.

 

nato.

 

ps give me a buzz if u like, chat more about it.

Link to comment
Share on other sites

Yep pretty much what Nato said RBZ. Have a look at the angles mind you if the car was rigged up for an alignment I would talk to the guys about the possible bump steer issue and they could show you what the problem is. My car used to wonder all over the place till I fixed it. Now it drives great except for the heavy steering.

I guess I can rig up the steering and see how it goes before looking at the idle switch. It sounds like it can be done afterwards. Like you say my motor might be able to push the pump enough not to have to go the next step.

Link to comment
Share on other sites

  • 2 weeks later...

found out what is the issue with the bump steer. I had a look at the angles and they pretty much perfect.

 

last nite had a bit of a look and clean up around the engine just to see what else i have to do on it. grabbed the steering rod just after the firewall and gave it a bit of a tug. to my shock it was fairly loose.

 

started to jitter the steering wheel and had approx 0.5cm movement. that explains the feathering on the outer of the wheels also bit of the dead band in the steering wheel when changing direcetions. even though alignement is good. dosnt pull where the road is flat. tried tightening the clamps but they were allready done to max.

 

looks like my custom bush got softer and has heaps of movement.  going to get some nolathane type mounts but not sure which ones as the z ones are round while the rack is square.

 

i wonder if someone knows what other people used. im going to go to my supsension/ steering guy after work today hopefully have something to sort me out.

Link to comment
Share on other sites

well my suspension guy wasnt there he left early and their check out guy was bloody hopeless. ended up buying a subaru bush and 240z bush and was going to join them somwhow and hopefully fix the problem.

 

started undoing the clamps and trying to replace the bush.

 

as i removed the two bolts something fell out. a spacer that i installed for some reason to lift the bracket. i cant recall now why i did it but i think from the heat and limited pressure on the rack just worked itself loose. i removed the spacers and tightened the clamp back on. this time it had lot of pressure on it and rack did not move.

 

the dead band was gone. steering  response was lot better and did not feel like a truck.

 

took it to the roughest roads at higher speeds and it was stable as. no more wrestling with it keeping it in line.

 

lot nicer to drive now than before. lot more direct and more solid feel steering. now to replace the tranny mount, get the tailshaft balanced and replace that damn loud Holley blue pre pump.

Link to comment
Share on other sites

Re mount your Holley Blue pump. I had one solidly mounted and it vibrated through the whole car. Drove me crazy. Then I mounted it on rubbers and that got rid of 85%. Now it is mounted with rubbers onto my moustache bar and you can't hear or feel it. Give that a try.

Link to comment
Share on other sites

yeah got soft rubber mounts mounted on the original fuel bracket.but still annoying. i dont want to hear the pump at all  ;D. just me being picky  ::) i may try to mount it ont the bar. as thats mounted on a rubber too. so may get rid of the rest. thanks for the pointer. if doesnt work as i expected there will be holley blue for sale soon  :P

 

otherwise i just may use vl turbo fuel setup. i allready have the high pressure pump from a VL turbo may get the pre pump as well.

Link to comment
Share on other sites

Power Steering here we come. Well I went onto ebay this morning and there she was. A WRX STI 98 Rack waiting for me in near new condition with 30minutes to go. A phone call later to confirm it's condition and suitability and one bid did the trick.

Anyway I dare say there will be a lot of work involved but should get it in and done over the next 3-6 months (I don't like to rush these things). But the car shouldn't be off the road for longer than 3-4 weeks since I can start using another cross member for butchering.

Thanks Ash for your offer through a mate but I figured for $202- I couldn't go to far wrong with this one.

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=280214731748&fromMakeTrack=true#ebayphotohosting

Let the work begin.  :)

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...