I used an '89 donor and went with an OEM power rack. I love the power steering but with the GT rack it is a tad twitchy. I have cut down the relief spring in the pump and that has helped some. As a winter project I may change it to a slower 4 cylinder power rack.
But yes, we do use power steering and I for one love it.
90 donor and power steering. Two best options during the build were power steering and brakes.
You will need to trim the spring some or add a reduceing valve/heidts valve to lessen some of the power.
Also be able to use more caster in the front end settings. This makes the steering wheel want to stay straight when going down the road. Takes the twitchyness out.
For power steer I went to +6 degrees of caster and MKIII handles like a cat on carpet,not at all Twitchy. Have you ever seen the caster on a Mercedes or BMW- My 528 BMW has +5.5 degrees and handles better than my MKIII !!!
W/ PS run as much caster as you can get.The front of the UCA will get close to the coilover spring and that will limit you.So then you start moving the upper coilover mount rearward w/ differnt spacer combinations. I even bent the rear mount rearward (more spacers in front) to move the coilover further. I guess, if you got to 9 degrees, you might say that's enough, but that would be very hard to do.
I agree that + 9 degrees would be tough to get but positive caster really changes handling and steering wheel response,very accurate at high speed with very tight feel. I've had no problem staying with (and passing) Porsche 911s and vettes. Caster is most under rated yet most important adjustment on these short wheel base cars. Read caster websites as is interesting how and why this works so well on track cars. John
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