I read about this mod in the forums (applied to a Mazda Miata) and decided it was worth a shot to try on my Talon. I've been driving on the modded rack and I like the feel, so I thought I would share how it's done. It's still diffucult to turn when not moving, but seems easier than other DSMs with looped power steering lines while in motion. When driving, I have no problem turning the wheel with one hand. The way the rack is depowered is by removing the inner seal that seperates the sides of the power rack and replacing the fluid with grease. Allthough I did this mod to a 1g rack I'm sure a 2g would be similar.
If you are interested in this mod, I suggest picking up an old rack or using a spare. The mod is irreversible. So if your rack is in good condition picking up a junk rack might be the best option. This way you can always go back if you don't like the feel of the depowered rack.
I won't go into how to remove the rack from the car. For that, see LSD's "How to" below.
1g AWD Power Steering Rack Removal/Install
To start remove both the outer tie rod ends. (This is not completly nessecary but makes the job much easier, rather than fighting with the boots when removing the inner tie rods)
Next you will want to remove the clamps and slide both the boots off the inner tie rods.
Underneath the boots you will see a staked washer holding the inner tie rod to the rack. Unstake these with a chisel and remove the inner tie rods from the rack on either side. I used an 1 1/4 wrench to do this.
Attachment 97841
The next step is to remove the end plug. Under the plug you will find another nut. Remove this also. On the other side of the nut is a bearing, this can stay in the tube.
Attachment 97842
Now I had to make a tool because I did not have an allen large enough to remove the rack support cover. I found a nut that fit in the hole and then found a bolt that threaded into the nut. They were welded together making them solid and I had the rack support cover removal tool. Using the new tool I held the cover and broke the locknut free using a large cresent wrench.
Attachment 97843
Under the support cover you will find a spring and the rack support. Remove these from the tube.
Attachment 97844
Unbolt the two bolts holding the valve housing on. You can now remove the valve housing. You may have to tap it with a soft mallet to get it out.
Attachment 97848
The next step is a little tricky. You will be removing the rack stopper. It is held in with a circlip. To remove the circlip I used a 90* pliers to rotate the rack stopper clockwise until the circlip came out of the tube.
Attachment 97849
Now you can remove the rack from the tube, it comes out the valve housing side of the tube. Once this is done we can now see the seal that seperates the two sides of the rack. To remove the seal I carefully used a cutoff wheel split the seal and removed it from the rack. Be careful not to cut into the rack. I used the chisel again here to finish the job.
Now is the time to clean, inspect, and grease everything that requires lubrication. Replace worn parts as nessecary. My spare rack that I used was in good shape so everything stayed together. This is where I cut the fittings from the lines and had them welded shut. I also cut the two fittings off the tube and had those holes welded shut for a clean look. Everything was now cleaned and greased.
Grease the gear on the valve housing, the bearings, the rack, and the rack support.
Slide the rack back into the tube and install the stopper with the circlip. To get the clip in rotate the stopper counter clockwise.
Drop the greased valve housing back in and tighten the two bolts at the top of the housing. Now tighten the nut at 14-22 ft lbs. You will have to hold the top of the pinion from rotating while you do this, be careful not to damage the splines. Reinstall the end plug at 36-51 ft lbs with sealant on the threads.
Time for the rack support. Apply sealant to the threads of the allen (rack support cover) and insert the spring under the support. Thread the allen in the tube. Here you will find if you thread the allen in too far the rack will be hard to move, too loose and there isn't enough support on the rack. I did this by feel as the Chiltons manual wasn't very clear on how to do this. When you are satisfied, lock the allen down with the locknut using the cresent wrench while holding the support cover in the desired posistion.
Reinstall the inner tie rods and stake the locking washers in two spots on the flats.
Lightly lube the insides of the boots and clamp them down to the tube and the inner tie rods.
Reinstall the outer tie rod ends and the de-powered rack back into the vehicle. Get the car aligned and enjoy your new mod.
"Miata Mod" on a DSM: De-powering the rack
