Power Steering

[racephotoman]

This may be one of my dumbest questions to date - I never installed the stock steering that can with the MkIV kit, but upgraded to powder steering at the time of the build. Now having approx. 3000 miles on the car the steering is very comfortable, but almost too easy - crazy? I would rather feel the road more - make sense??? Anyway, short of exchanging the rack to only discover I want the power back, are there different power steering pumps available (here comer the stupid part) that offer an adjustment or less assistance to the power steering unit so I could feel the road more?

Walter

[pcww]

Check out the Heidt's valve which allows an adjustment of the flow to rack. I assume you have the Ford pump. For the GM Saginaw pumps there are also various adjustment "stuff". The only place I have seen these is at Speedway IIRC.

[CraigS]

Couple of options for you. 1-First and cheapest is drop the front tire pressure. I have been a slow as 16# but probably would say 18# is a good minimum. 2- Adjust as much positive caster in as possible being careful to have enough threads inside the front sleeves of the UCA. May need longer front sleeves. Anything up to 8-9 deg will help. 3- You can reduce the pressure in the PS pump by cutting the relief spring. There is a length recommendation somewhere for a stock Mustang pump. Otherwise, pull it out and cut one coil off and re-shape the end to original contour. Put that end in the plug so, if you don't have a great end done, it won't matter as much. You can cut more off if this isn't enough but, while it is out, find some small washers that fit in case you cut it too short. A few washers will shim it back to normal or to your last step. good luck, you are on the way to a great driving car.

[skullandbones]

Hi Walter,

All good advice so far. Here is a pic of my setup with the by pass valve for the PS pump. It's really one of the best things I've done on my project.

Good luck,

WEK.

[Jeff Kleiner]

Heidt's valve if you want the ability to adjust the amount of assist for varying conditions &/or drivers:

http://www.heidts.com/part/adjustabl...-valve-ps-101/

Trim the pressure relief spring as Craig described if you want to "set it and forget it".

I've used both methods on different builds.

Cheers,
Jeff

[jceckard]

So, if you were to use a heidts valve with a hydroboost power brake get-up, would you run the pressure line from the pump to the hydroboost, then to the heidts, then the rack?

[CraigS]

I don't remember the plumbing diagram real well but I hope there would be a way to just reduce PS assist w/o changing braking assist.

[edwardb]

So, if you were to use a heidts valve with a hydroboost power brake get-up, would you run the pressure line from the pump to the hydroboost, then to the heidts, then the rack?

The use of a Heidts valve along with PS and hydroboost is discussed in a number of threads over on the other forum. The short answer to your question is yes. The first stop for the high pressure line from the pump is the hydroboost unit. From there, high pressure is fed to the PS pump, and that's the high pressure line where the Heidts valve would go. The return line from the hydroboost would be used for the return side of the Heidts valve.

I've seen the "cut-spring" mod talked about a lot on both forums, but don't recall it being talked about along with hydroboost. Obviously that mod affects the pump output directly, so both systems would be affected. Within reason, I'm not sure that's a problem though. I have Fast Freddie's EHPS system on my Mk4 driving both the PS and hydroboost. In that setup, there is a valve on the electric pump to adjust the amount of boost. I felt that the PS was a bit over-boosted at first, so turned down the pressure slightly at the pump. It made the change in steering I was looking for, and best I can tell the brakes were not affected. They are very strong. Without citing pressure numbers (because I have no idea what they would be...) it seems the actual pressure requirements for hydroboost are not extreme, plus they have an accumulator that stores pressure allowing some power assist even without pressure.

[racephotoman]

did purchase the valve and more hosing - will install shortly - to all, thanks for the advice and help!
Walter

[mcwho]

skullandbones,
I am looking to do the same with my MK4, i have the GM integral ps pump and a 87-93 power rack from breeze. Looked at the Heidt site, they have a hose kit but it says its for a mustang II rack, and i think those have 14 and 16mm connectors.

from what I i have seen the rack may be 9/16 and 5/8 but not quite aure. hose did you sort it out?

ill also send a PM if you like

[Jeff Kleiner]

Fox rack is 9/16" and 5/8". The appropriate AN-6 "O" ring fittings are available from Breeze.

Jeff

[mcwho]

Jeff, (and others)

I have the Saginaw pump AND the Heidts valve also, I have the Heights cranked out to what should be minimum pressure. Going in for first alignment next week, so this may be premature, gonna set front tires at about 22 lbs. Hopefully that will make my stering less touchy.

I also want to look into the spring in the pump mod, as long as I can get a new spring in case I don't like the effect.

[Jeff Kleiner]

No need to modify the spring; the Heidts valve will allow you to adjust the assist level.

Jeff

[Chuck Sloggett]

I have hydroboost with power steering. I use the stock pump with a cut the spring (7/16" if I recall) and have just the right "feel" for steering and the brakes work great. I use Honda fluid and the pump is silent. -- Chuck

[CraigS]

1 and 7/16 inch is the standard recommended length. If by chance you cut it a little too much you can shim it w/ small washers.

[mcwho]

My first question, how easy 8s it to get a new spring if you decide to go back to stock setup?

I did some checking and haven't found it as yet.