bobbigham

I was wondering if there was a difference in power steering pumps and if it was possible to improve power steering assistance.

In a previous thread (couldn't find it in search) someone mentioned that in 91 or 92 the steering got "high output" power steering, or something like that.

I noticed that there is such a thing as "high output" rebuilt pumps for sale (928 Specialists) for less than $200.

My issue is that my 88 928s4 seems to have very heavy steering at low speeds, certainly much heavier than my 97 993 (I know, the 993 has no weight in the front). The feel is good, but just seems very heavy. It currently has no leaks, no noises, apparantly no problems.

Would replacing the current 88 928s4 pump with a "high output" or later model (92 or later?) pump help lighten the steering a bit? Is it a tough job to replace it? Has anyone tried this, noticed the difference between newer 928's versus older 928"s???

the flyin' scotsman

The higher o/p strg pumps were fitted to the '91 and newer models and as the belts are the same I believe the brackets must be the same so you should be able swap.

bobbigham

I was hoping they would be the same.

Anyone know if the HO unit acually improves the assist.

I forgot to mention that I have 9" wide front rims with 235/40 18"s, which really shouldn't cause the steering to feel too heavy. Just thought I would add the information here.

the flyin' scotsman

I don't have personal experience with swapping LO to HO but there's a significant difference in pressure 75 vs 100 bar (91 Tech Spec)

SeanR

If you replace the upper power steering hose on your 87 with one that is "made" for a 91+MY, the steering will be easier. The restrictor on the 87-90 hose is not there in the 91+.

I know PET and 928int say that you will need to replace with the same part number, but the newer one is a much easier install and works just great. Not to mention that there is a $100.00 difference in price.

When mine was leaking I was over at Rog100's and looking at the menagerie of cars he has and we discovered that someone had done the same thing on one of his stock, so we decided to give it a try. The pumps are the same externally, as far as fittings is concerned, the only difference in mounting is the newer one feeds more towards the rear of the engine compartment and you will not be able to use the bracket on wheel well as was done in the past. Don't worry tho, this presents no issues and my steering is much lighter.

bobbigham

SeanR, do you mean if I replace the pump with a HO one that I should replace the upper hose with the later model one as well? Or did you mean just replace the hose? If I replaced my 88 pump with a 91+ my pump would that be the same as replacing with one of the rebuilt HO pumps?

Thanks for the information.

mcholdfast

I replaced the rack in the GT with a 91+ MY Porsche rack and the difference was tremendous. It was a bit confusing at first because most suppliers only list racks for 78-81 and 82-95 but if you ask the dealer, they list a different rack for 91+ cars. Don't ask the dealer for their price for one though. I was told they only had new ones for 91-95 and no rebuilt ones available. Nicole started a very informative thread about this a while back here. My guess is that the rebuilders only offer the 82-90 MY rack for all cars 82-95. I got mine from Devek as they were the only ones I found that had them available at the time. I also bought the Griffiths HO pump but it's still in the box. Once the later model rack was installed, I didn't think it was needed. I'll save the pump as a replacement for whichever one fails first. If you want to take the GT for a spin, you can feel the difference for yourself. It also has 9" wheels up front.

Bill Ball

I'll second what Mike reports about the rack. I helped Nicole with the 91+ rack installation after trying a rebuilt rack, and the 91+ provides reduced effort. Nicole already had the HO pump and hose, yet the rack made a significant difference. Combine that with the HO pump and hose.

bobbigham

That would be a good way to compare. I would like to see the new paint job anyways.

I didn't think the rack would make a difference because it already feels tight/ firm, but my steering is so heavy (and more of an issue at low speeds), I thought it would be the steering pump...not sure which change I would hope would work best?

mcholdfast

How's tomorrow? It looks like it's gonna be another beautiful day for a drive. I'm lovin this weather.
If the HO pump and new lines made enough of a difference to satisfy you, it would certainly be less expensive than replacing the rack. The steering effort on my S4 is similar to what the GT was before so I may try the HO pump on it and see what difference it makes. My only concern is that the HO pump may create a leak on the older MY rack given that it is pumping at a higher pressure. Is anyone out there using the HO pump on a 90 or earlier MY? Any thoughts from the gang about the risk of the HO pump making an old rack leak?

Bill Ball

I think lots of people have put the HO pump in w/o issues. You're right about the 91+ rack being expensive. Unless the current rack is leaking or worn, I'd leave it alone.

RngTrtl

Just a thought. I have an '85 and the PS is superb and it takes only hardly any effort at all to steer at any speed, even stationary it is easy. I am wondering if it is just the pump getting old. If that is the case then just replacing the hose (that does not have the restrictor) might help some, but the pump is liable the give up the ghost soon.

ROG100

I noticed a big improvement by just resealing the existing pump/pumps.
Cost about $25 and takes 30 mins after pump removal.
Rennbay sells the kits and has full instructions.

SharkSkin

Bob, you did check to make sure your belt isn't slipping, right?

bobbigham

No, no problem with the belt. Not sure if replacing seals, etc would help as the pump isn't leaking any now. A hose and a rebuilt HO pump isn't too prohibitive.....

Sorry Mike, it was a beatiful day and I got busy washing the shark and 993. Next weekend maybe?