heinrich

Hacker, many 944 parts fit as a bolt-on to the 928 --- may wanna look into it. I bet those racks are super cheap too.

Aspkiller

Be very careful!! First it will be a different steering rack and the next thing you know, it'll have a Chevy engine.

hacker-pschorr

You read my mind. My 79 will be up in the air this winter with God knows what removed. I know where there is a busted 944 rack that would be good enough for mock up.



With my luck I'll wake up after a drunken stuper and find the engine from a Renault Dauphine under the hood.

heinrich

LOL Larry

blown 87

Granted, but you do not see stock cars and most race cars that weigh 3000 LBS with out power steering either.

Lizard928

I drove my 81 track car without power steering for a long time.
I also used a 350mm momo steering wheel......

The slow speed was OK, once moving was great, and on the track was awesome.

if you want to build a manual rack, have a machine shop take a piece of chromoly and cut different teeth into it (or modify a factory rod) for the different size of teeth, then have them make a new solid shaft with the helix on the bottom to give it the different ratio.

I know someone who did this with the 924 rack, iirc it ran around $1200.

I was actually interested in a tighter ratio rack as a manual rack, I was less concerned with the effort, but more so with requiring less rotation on hairpins.....

justaguy

The 928 is a heavy pig on track and you're constantly fighting the mass of the car.The widow had power steering and took serious effort to get the thing to turn. I tried racing a 928 this year with no power steering it was a real struggle and not enjoyable.I will have power steering next year.

marinesniper0318

88, S4

My rack had a leak recently and I found out just how tough it is to turn the damn car in a parking garage, I almost hit a couple cars and the wall. And I am not a weak guy, 6'0 260lbs muscle and it irritated me to drive it without assist, it was just to dangerous for Miami driving... : )

So my baby's steering issue is getting fixed...

sniper

hacker-pschorr

How much does the widow weigh?
Did you do anything with the alignment for manual steering? I ask because I've seen on other forums with cars that are more likely to have an option, caster is greatly reduced without power steering to reduce the effort.

blown 87

The flip side of that is they get kind of weird handling when you take the caster out to make them easy to steer.
They also get really weird when you add power steering and do not have enough caster, as I found out when I added power steering to the Chevelle and could not get enough caster due to the big tube headers.

FBIII

Here is the post from the 944 site describing the 944 steering rack.
Coming from a recently reassigned hydraulic power steering engineer of 4 years...

How to turn a power rack into a manual rack and actually live with it:

1. Piston chamber - must remain filled with POWER STEERING FLUID in order to keep seals sealed and bearings/bushings lubricated. Proper way to do this would be to remove the stock lines and plumb them one into the other. Since nothing will be pressurized, you could literally cut the lines and just use a ps friendly hose and clamps to connect. The chamber must be 100% bled free of air, or else you will get a nasty feel as the trapped air rushes across the piston seal and froths up your fluid making it spongy. Running both lines to a common resevoir would be the best way to keep it bled properly. If you don't disconnect the piston ports from the valve ports, you must force the fluid through the valve before it can get back to the low pressure side of the piston. This is about half of what makes a PS system with the belt disconnected feel mushy and overly heavy. That is as long as you still have fluid of course.

2. Pinion tower - 4 ports on this. Plug up three of them and run the fourth (highest one) to your resevoir. This area also needs to be kept full of fluid to properly lube the bearings. There is no "pumping" action up in the valve tower when unpowered.

3. Valve/pinion drive flats shim - the pinion (gear that engages the rack) and the valve (part connected to the input shaft) are two separate parts that are joined by a torsion bar. With the pump running, when you twist the wheel, the valve senses the amount of torque you're inputing to the rack and provides an increasing amount of assist as the angle of twist in the torsion bar increases. There's usually about 15 degrees of twist allowed before the valve reaches a mechanical stop on the pinion called the drive flats. This mechanical stop is there to limit the max amout of twist in the event of a pressure loss or torsion bar failure. When you disconnect your PS pump, you obviously loose all assist and must now twist the wheel through that 15 degrees or so in either direction before you can apply anything more than a few ft-lbs of torque on the steering wheel. This is a large factor in the "mushiness" felt by those running PS racks without the belt connected. The easy fix is to just take up the free rotation between center and each drive flat. This can be done with shims relatively easily.

4. Boots/rack teeth/equalizer line - Boots must be intact and sealing properly. Their entire job is to protect the inner tie rods, and they need to do this on both manual and power racks. Slather the rack teeth with a healthy amount of sticky grease (moly works fine), but definitely don't pack it in. And you must keep the equalizer line installed and intact. This is the line that transfers air from one boot to the other as the rack is stroked. If you leave this off, you may as well just run without boots and plan on replacing your tie rods every few months.


And that's it. Summary: you must keep fluid in the rack to keep it from eating itself to bits unlubricated, disconnecting the piston ports from the valve ports will lower turning efforts, proper steering maintenance items must still be attended to, and install shims to remove the free play in the valve/pinion assembly.

After you do all that, you should have a "true" manual steering rack (probably with a heavier ratio), that should last for a long time.


DanG
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10-13-2005, 06:21 AM

xschop

You guys do know the 928 is rear steer? I modded a Tercel rack for a 944 track racer before using Borgeson joints. IIRC an old jetta is rear steer and 11/16-40 just like the 944...What is the spline count on the 928 rack?

heinrich

What the hell are you talking about Dude?

hacker-pschorr

I had to look it up too:

http://fsae.com/eve/forums/a/tpc/f/1.../m/21210681341

I was aware of different configurations of racks, just not these terms....interesting.

justaguy

The widow weighed 2980lbs had power steering and was a dream to drive compared to my current supercharged race pig ,sorry ,car. I was not aware of how to change the caster to make steering easier.