danglerb

Steering rack seems like kind of a simple mechanism, turn this, and the ends go in and out, what makes the one on the 928 special?

RyanPerrella

its dimensions

RyanPerrella

please dont start trying to re-engineer this to. They are fine, dispite what a few people would tell you. When they leak, buy a rebuilt one with a warranty, end of story.

danglerb

ebay $1.94

RyanPerrella

YES??????

fabric

While this does seem like one of your more obtuse topics, a lot of people do like the ligher feel of the later racks, so I can say that getting a higher output pump and the lines that have less flow restriction would provide a tangible change in the steering feel, so in that ways, I will grant that there's room for change in the steering. But the rack? You're just buying trouble trying to fit one not designed for the 928. As you said, the rack itself isn't anything special, but neither is any other rack you'd put in it.

lorenolson888

The rack is fine and many racers will tell you to run the car with no PS... or maybe a low output pump...

I think if you want to engineer something figure out how to use an electric PS pump. I think someone has done this... I have seen one that is for boat steering that may work...

Loren

danglerb

TRW made a PS rack that was electric, but no idea what became of it in a Luddite world.

I am just curious in general about which parts are special, which do a great job, and which might have better options. Nobody seems married to the factory brakes or tires, why should any other part be considered holy?

In this case it seemed from other threads that some people were not entirely pleased with the rebuilt racks, so I wondered if the rack has some problem unique to it.

*** link to info on TRW http://www.autofieldguide.com/articles/090602.html

RyanPerrella

there are no unique problems, the rebuilds come because seals have dried up and leaks start to occur.

I agree with the idea of the electric pump, but that in turn requires an electric rack. (Good luck finding one to fit) The electric pump would eliminate all the PS line leaks, which are pretty common, i havent seen a 928 that hadnt at some point leaked there. Although they are easy to replace and the pump is a sinch to refresh.

What do you think a new rack will do for you? If we were talking recirculating ball, you may have a point to add a rack. But if Porsche never fitted a rack then there was some other reason why. These cars spent many more hours in R&D, and i certianly trust their judgement to go with the rack thats in the car then try and fit a VW rack in my porsche cause its $1.94 on Ebay. I guess you suppose that your idea would be superior to Porsches. Of course you have these ideas from old Rennlist postings.

I would love to meet you, I have to put a face to your posts, I CAN ONLY IMAGINE WHAT YOUR LIKE OVER A BEER!

BC

An electric pump would work with the stock rack. The pressure would need to be carefully figured out. And it drains quite a bit of power.

danglerb

Beer makes me less shy and reserved.

RyanPerrella

your hardly reserved

John Veninger

No 928 racer will tell you that.

jon928se

ZF makes the best racks

Guess who made the 928 rack ?

It's a shame that Porsche didn't see fit to use a ZF auto box in the 928 or for that matter a Getrag 5sp.

fabric

On the S4's at least, the factory brakes are Brembo's. When it comes to brakes, people with out the S4's tend to upgrade to S4 brakes, and if somebody deems it necessary to upgrade the S4 brakes (which is unnecessary unless you race, really), they move the the GTS brakes, which are just bigger Brembo's (and where also spec'ed on the 911). Which ties into wheels, you can't fit 15 inch wheels (which some of the OB's have) over the S4 brakes, and you can't fit 16 inch wheels over the GTS brakes. Relatedly, people just want bigger wheels, it has nothing to do with what came on the car being bad - in fact, I think the stock wheels on my S4 are the best looking, and don't want to change them, I'm just worried that I won't be able to find 245/45/16 tires in a few years. In fact, the stock S4 wheels are forged aluminum and very light, something you don't see on mamny cars - the GTS wheels are cast aluminum. And I"m sure you've seen posts about the Club Sport wheels, and how desirable those are in the 8" and 9" widths. This whole argument is pretty much a non-starter, and the brakes and wheels particularly so.

Again, Ryan made the point about Porsche engineering - this isn't a Honda Civic. Porsche put the best on the 928, it was the their top of the line model and competed with Ferrari's and Lambo's for sales. They didn't put basic parts on it, they put on top end stuff. There's few areas you are going to build a better moustetrap than Porsche did, and I would suggest if that's what you want to do, look for things that are lacking, not that are already there.

And the idea of the carbon fiber torque tube has been thrown out before, so you can search for the thread on that one.

If what you want is the latest, greatest technology for the sake of having it, I"m afraid you've bought the wrong car. But the 928, stock, is still a technological tour de force in terms of engineering and performance, and the improvements you can make it are a matter of degree, not kind.