rmr25

I've been trying to reduce the steering effort on my S4. I installed a Griffith HO pump. Steering effort was reduced a little, but not significantly. I did not replace the factory high pressure hose with the restrictor feature. The rack is a rebuild about a year old, showing no leaks.
Some have suggested using the '91 and later hose without the restrictor. Maybe that's my next step. But I wonder if it's possible to cut out the existing restrictor and replace it with a simple barbed connector and clamps? Or would the barb merely add restriction back in? Does anyone know how much "restriction" the restrictor actually imposes?

Garth S

I suspect that standard barbed connectors will offer considerably less pressure drop than an OEM restrictor hose ... note that word 'suspect' - for I have never cut one open to measure the effective orfice size.
Are you still using a smaller diameter steering wheel?? If so, it will be a long and likely futile fight to reduce low speed steering effort. Also, are your front wheels of the OEM 65mm ET, or reasonably close to that? ---- and tires of 225mm section?

Lizard928

best way to reduce steering effort is to go to a gym and get a membership and spend a few hours a week increasing the strength of the nut behind the wheel :P

all in good jest, I run 245 with 52 offset on the front of mine, with NO power steering.

SeanR

Just purchase the later style hose, it's only $120.00 and easy to swap in and out.

Or, if you have the time, take your old hose to a hydralics place that rebuilds them and just have it all redone w/o the restrictor.

rmr25

Thanks Guys for the suggestions.

Garth: Front wheels are OEM 65 mm ET, tires of 225 mm section. Also, I have recently set the car's height correctly and had front/rear alignment done by competent local shop. The steering wheel is 350 mm diameter.

So-o-o-. Just for the test of it, I will cut out the existing restrictor and replace it with a brass barb and see what the effect is. If steering effort is not reduced, then I'll install the later non-restrictor hose. That way, at least we'll all know more about the restrictor properties, dimensions, etc.

PorKen

IIRC, you can get special hose clamps for high pressure? That line may pressurized to upwards of 3000PSI!

rmr25

If the pump output is 110 psi, where does that "upwards of 3000 psi" come from?

backnblack

Hey Bob where did you get that pump and what did you have to give for it ?

rmr25

All the information is here: http://www.griffiths.com/

Lizard928

rmr25, that is 110 BAR, not PSI, huge difference.

ColinB

I want to fit a smaller steering wheel so I'd like a slightly lower steering effort and I was thinking of removing the restrictor but I've been told doing so might produce odd noises. Anybody had this experience?

Colin. 89GT.

rmr25

Restrictor-less high pressure hose now!

I removed the restrictor and replaced it with a brass barbed splicer and heavy-duty hose clamps. I judge the steering effort now to be about 20% less without the restrictor. I notice no strange noises or stuttering at parking lot speeds. On-road speed sensation is as before. Parking and other slow turns can now be done with one arm, versus two before! As noted above, I've got a 350mm sport steering wheel installed.

For those interested in the dimensions: Hose id is 9mm. Restrictor orifice is 4 mm.

Cost: $2.50 for the barb and clamps at a local Fastenal outlet. (They're also on the Web for on-line ordering and hose replacement work as well.)

Finally, the Griffiths pump is 100 bar, which is about 1400 psi. My Mistake!

Garth S

Well done! If staying with clamps, two per side rotated 180 deg will make a more secure connection.

By way of comparison, my '80 with 225's on 8" fronts steers far easier than any S4 I've driven ( with their stock 70 bar pumps). I thought the early 16v had a 70 bar limit too ... must check later.

Mrmerlin

I would suggest that you dont cut the line it runs very close to the exhaust header and it gets hot ,if you put a clamp /fitting on a hot hose thats under pressure it may very well seperate, and we all know how well dextron 3 ignites, I would get the newer hose and install it with some heat shielding silicone unless it already has it, also its a good idea to add the bumper to the top of the bend where it rubs against the inner fenderwell, the new hose should have this part as well, unless you get the hose replaced at a hose shop

macreel

rmr25... steady-state pressure runs about 1,500 psi (~100 bar).
Higher psi can be from transients, easily double.

G'luck.