Steering Is Stiff In R32 W/ Rb25 Pump And Hicas Removed

[Delux_247]

Hello all,

My 90 R32 GTST has recently finished getting an RB25 swap. During the swap it was decided that we remove HICAS and use the RB25 power steering pump (from a C34 if that matters).

Unfortunately my steering is quite stiff, not to the point where I would say not working, just not working properly, the wheel does not return freely. What could cause the heavy steering?

What is the motor or sensor that is connected to the steering rack? Cause its not connected at the moment (what does it do?)

The Hicas ecu is still plugged in, however I snipped the green wire on the smaller plug to turn off the dash light.

Is there some sort of steering speed sensor that needs to be connected? where is it located? (could possibly be connected still just throwing out ideas)

I also have an aftermarket hub and wheel put on at the same time as the swap, Im pretty sure the hub was for an R32 with hicas but i cant be sure... the turn signals do go off when i turn straight though.

thanks!

Edited December 16, 2009 by Delux_247

[Delux_247]

Well we plugged in the solenoid on the rack and made sure the wires were conductive and still pretty heavy.

So, I have been reading that if the HICAS ecu reads something wrong it will go into limp mode right? well I all the lines and anything related to HICAS except the HICAS ECU and rack solenoid have been removed. Will it always be in limp mode?

Do people that have HICAS removed just have to live with the heavier steering? (Ive learned the heavier steering is because the car always thinks is traveling fast and so it stiffens up the feel?)

[bubba]

The steering angle sensor thing could be out of alignment but this will usually take a couple of minutes of driving before it throws an error.

Did you put a 25 box in aswell? is the speedo working correctly?

Do you get light steering for a couple of minutes or is it heavy from the get go?

[Delux_247]

the feel of the steering never changes, never is light then gets heavy. Just always heavy.

i have an rb20 transmission and the speedo works fine

at the same time I installed a r32 boss hub and nardi wheel, it turns off the signals just the same as the oem wheel did(the oem wheel didnt turn off the turn signals all the time but the steering felt fine)

is the steering assist thing on the rack controlled by the HICAS ECU? where can i find a wiring diagram for a gtst?

[DFAULT]

Same problem as i had

Was a headache working it out

You can run 5v directly to the steering rack

I can find out which resistors we used

[Ben101]

could also be using rb25 pump on a steering rack not built for it each series of pumps put out different flow rates perhaps look into changing the rack over

[Delux_247]

Same problem as i had

Was a headache working it out

You can run 5v directly to the steering rack

I can find out which resistors we used

that would be amazing if you could!

I wouldnt mind the steering if it was a track only car, but being a daily driver its a pain.

[Delux_247]

could also be using rb25 pump on a steering rack not built for it each series of pumps put out different flow rates perhaps look into changing the rack over

Ive also briefly thought of this.

we've noticed that the return line is large, and thought maybe changing it to a smaller size would increase the pressure and help out. Of course too much pressure and we would blow the seals...

another thought was to do the s14 rack conversion

Edited December 23, 2009 by Delux_247

[Ben101]

There is a brass restrictor in the supply line to the pump perhaps removing that could increase flow?? but as you said could be to much pressure and blow seals ?

If you do the s14 conversion you should be able to get rid of the hicas computer i think meaning if speedo cable breaks it won't affect the steering making heavier you have to check what controls the pressure on the s14 rack example on a track day doing 140km/ph you don't want super light steering it needs to ramp up slowly that could all be controlled by the s14 pump not sure haven't seen one .

[Sheriff Wan]

Im doing this conversion right now, and have encountered the need for the rb25 pump as the balancer has 3 ribs for power steering and the rb20 pump is 4 ribbed...

Would love to know how to keep the steering the way it was, could you use a 3 rib belt and the rb20 pump?

Or has anyone solved this one?

[Ben101]

Im doing this conversion right now, and have encountered the need for the rb25 pump as the balancer has 3 ribs for power steering and the rb20 pump is 4 ribbed...

Would love to know how to keep the steering the way it was, could you use a 3 rib belt and the rb20 pump?

Or has anyone solved this one?

I recently removed the hicas system on my r32 and decided to use the smaller pump off a rb25 but they have the different ribs, I then got the rb25 pump removed the shaft( its shorter ) got the r32 pump removed the shaft ( long shaft ) pressed off the pulleys swapped the 4 rib pulley to the short shaft re-installed removed half the body off the r32 pump use the back cover off the rb25 bolt it back together needed to grind the back plate to refit into r32 backet and not a problem steering is the way it was before

[Sheriff Wan]

Excellent - thanks very much

[NZM.031]

im doing this at the moment.. but im using an s14 rack and pump to do away with all the hicas shit, it also has a nicer plastic resovoir, looks a bit neater ... the rack doesnt have the solenoid and is 1kg lighter, there is only the one pressure sensor in the line... apparantly the s14 rack has less turns lock to lock but i wont know till its all done.. the s14 pump has a seperate pulley (not attached to the shaft) so i can change it with a nice aluminium one, either 3 or 4 rib, depending on what the balancer has.. im also mounting it down low, where the a/c used to be...

i will be making a build up thread now that im getting things done and my brain is starting to kick over.