Captain_Slow

I, too, thought the Delrin bushes didn't look like much, but the stuff is really tough. It may cold-flow over time as Dr. Bob and Carl mentioned. See how they hold up over a couple of races or until you feel less precise steering. Your findings will be interesting. The Delrin were and continue to be a huge improvement over tired and oil-soaked originals on my S4.

mark kibort

well, i cant imagine it being any worse. basically, those inner cylinders were floating in air and the rack was moving all over the place.
Ill be buying my second set of new tires , since 2001. so, illl have some Big grip which should alow for a test , at least one day. certainly ill be sensitive to the change, since i now know what is really bad..... as Fred said, he understands not really noticiing it being so bad on the track, but what i got used to is just the amount of steering angle i needed. again, thought it was 928 being an old car and poor steering ratio design. but on the street, i was thinking it was a little weird that i needed 45 degree steering angle to make a lane change.....

FredR

New tyres also help!

The trouble is you get used to working around whatever handicaps one has to deal with and compensate autmatically - then when things are as they should be it will be interesting to see whether you benefit from such or struggle to get your head around the way the thing now works- oversteering and end up scrubbing the new tyres as you bunny hop round the corners [hopefully not].

The only certainty on a race track is the stop watch - it never lies.

mark kibort

hahahh ... "bunnyhop" While true, ive been down this "road" before.. you can set your watch to my times. nothing ever is very surprising. this car is like a second skin, no matter if things are connected or not! the forces of steering will improve handling, im convinced. however, it will change the huge angles i had to move the steering wheel to run around sears point. and so much at the hairpins, i almost had to shufflesteer just to get the wheel turned enough! the wear thing started bothering me... that, i thnk will be fixed. cant wait... tires on the way today!!!

dr bob

Illiteracy is a scourge facing the nation. More and more people don't know how to read unless it's thumb-glyphic abbreviations on a tiny screen. When presented with very clear precise statements with justification, the brain goes numb and causes other actions.

Mark, if you actually wanted guidance but had already made up your mind, why do you waste our time asking the questions?

mark kibort

Bob,

I agree, and am even more suprised , that besides reading and comprehension, the world cant think for themselves when the facts are so readily available to make decisions. and draw conclusions.

Clearly you are not thinking through your response. Just because you have the best solution, doesnt it mean it is the RIGHT solution for anyone. If it was, we could just ask, you or I for an opinion /information and they would take it without thinking. However, there were other factors that, ironically, you must have missed. I asked the options because i didnt KNOW the options, so thank you for the answers. Much appreciated. However, based on my assessment of the factors, i was not able to use your suggestion... dont take it personally.
Also it was presumptuous for you to say that i already made my mind up.
I only had one shot at this... and limited time to about 2-3 hours... so, i made a choice.. it was a good one..... based on MY limitations. (not a $ thing, only a time and effort thing)

So, I'm sure the list will benefit to see how long or the wear pattern of the steering rack bushings made from plastic .

Do you think the aluminum bushings can be installed from the top and pressed into the holes with the nuts and bolts being tightened? if not, ill have to account for much more time to completely remove the rack to knock them in to the holes.. top and bottom.

do you understand the logic now?

thanks for the input.. always valued.

Mark

dr bob

Clearly I thought through all responses very carefully. Had you asked here if the ears on the rack need to be machined to get the al bushings to fit, you would have quickly received an answer. Had you asked the vendors, you would quickly receive an answer. So clearly you did not think through the results carefully.

Good luck with your project! Replacing the worn/squeezed Delrin with aluminum later won't be nearly as much work as it was getting the old original rack bushings out. You will probably want to do another minor alignment adjustment when that happens, as even minor changes in rack height relative to the spindles will change your toe.

mark kibort

I didnt mean to come across flipant.. thanks!
you said this. maybe i misunderstood your advice:
.were you saying that by pushing the rack up with bolts through the bushings yo could just press fit the bushings into the holes? they were pretty hard to install, as the fit is , as you say, an interference fit. maybe i missed that, and didnt need to bang them in. if so, not much loss. the hardest part was removing the remainder of the stock bushing outers.. ... the next time will be very easy, especially with that allen wrench trick to hold the bolt.

i still dont get what you were saying about he "ears". my question really has to do with installation of the aluminum or delrin bushings. press fit by using bolts or banged in with wood block? that was my real question

i see what you mean about the alignment. ill check that tonight

thanks again.. and never worry.. always apprecate the help and info.

dr bob

Mark --

The bushings install into the aluminum mounting "ears" on the rack. The fit is zero interference so they will fit with no play. The ears are pressure cast as is the rest of the rack housing, with the holes in those ears part of the casting process; no additional machining is done. Will there be variations? Can't guarantee that there won't be any. But the several sets of bushings installed in clinic cars including aluminum bushings were all done with no additional work on either the bushings or the ears. I think maybe half a dozen or so examples for statistical purposes. Maybe others will report different results. So far all have gone in using the bolts. Worst case might be one that needs a little extra squeeze with a C-clamp or something. I think the fit around the bolt was as tight as the fit from bushing into rack ears.

Regardless, you chose what you chose, installed what you chose, and see an improvement from what you chose. How they hold up under high heat and pressure is yet to be determined. Know that there are aluminum bushings available to solve the known cold-flow problems with the Delrin under extreme pressure and heat. Should that need arise.

michael j wright

Many thanks for the tips, DrBob and others. that allen head wrench trick to stop the tops of the hex bolts, was a deal saver. 2 of them were unreachable by the the box ends.

read for laguna seca with the new car!! [/QUOTE]

I will be needing to do this also. So what is the trick to do this that you are talking about?
Thank's Mike

mark kibort

I will be needing to do this also. So what is the trick to do this that you are talking about?
Thank's Mike[/QUOTE]
the trick, as i heard and did, was to put the allen at the point where the top of the bolt, starts to rotate and get close to the structure around the bolt. it locks it in place. . easy to start it spinning with the electric drill and socket, and move the allen around the area where it can make contact and "jam " between the bolt and the chassis. then, its in there and you can tighen with a normal socket wrench as you hold the allen in position, partially jammed.

i noticed the delrin bushings had a tight clearance , so i hammered the bottom side into the ears. then the bolt had a hard time coming down into the hole that kind of closes up a bit. with out being in the ears, the bolts slide into the bushing pretty easy. so are you saying, when you do the rack, both the upper and lower pieces are not pressed into the ears, or do you press them in while the rack is off the car. again, my question has to do with putting the bushings on , with the rack stilll on the car.

michael j wright

Thank's for the answer Mark, that helps a lot! Makes sense as a way to hold the head of the bolt rather than trying to get a wrench into position.
Thank's again-Mike

mark kibort

its not obvious of which ones need it.... but, as you are laying on your back, head toward the rear of the car... the rear driver side bolt can use a box end to secure.
however, the one forward to the filter , needs the allen.

the other side , both need the allen. they both are pretty open but that damn frame work is just not wide enough to easily fit the box end.

dr bob

Mark--

Worst case (so far) got a "squeeze" from a c-clamp to get both aluminum bushings seated in the rack ears. I then let the roller jack and a block be my third hand, supporting the rack in the middle to hold it in place while the bolts were fitted from above. I played some with the bottom shield in or out during initial lift but settled on leaving it out so I could see to fit the bolts. Then hold the rack up with one hand, roll the jack out and then fit the plate with the other. Just finger-tight on the big nuts first, then the smaller nuts on the t-bolts and the bigger bolt at the driver's end of the plate before torquing all the bolts. With the Delrin bushings you might consider a little less torque on the four main nuts, as it feels like spec torque is squeezing the Delrin a lot. You'll feel what I mean when you do the last tightening-- the last few twists on the nuts seem to not need increasing torque. It's causing the Delrin to flow out a little rather than compress.

michael j wright

Thank's again to both Mark and DR Bob. Will be diving into this in the fall, to hot at present.
Mike