Rob Edwards

Rob-

So how good a baseline (ie- ride height and alignment) do you have to have before corner balancing? Doesn't the process of corner-balancing affect the ride height, and how do you do it without lifting the car? Do you drive on the scales and try to adjust each corner without lifting it?

I got my shocks re-installed last night but need to go find Bill's posts on what to torque when while getting the car back on the ground, and then I figured I've got a few rounds of ride height adjustments to get it close before going and getting it re-aligned. Were I to do a corner balance, would that be done AFTER all of the above?

(Sorry for the ultra-newb questions).

928SS

it's a bit of a process - get car sorted/settled, put the car on scales, get stats, do the math, pull it off, jack it up, pull the wheel, adjust spring, replace wheel, then drive around to resettle, then back on the scales, recheck. repeat as necessary.

the ht does get affected somewhat, not much as it's just 1 or 2 corners that get most of the adjusting.
prolly best to swap out all the stuff you are gonna change, put the car into "normal" trim (fuel, tools, etc for whatever type of driving you are tuning for), set ride ht, get everything settled, do the balancing thing last.

took about 90 minutes for mine, but well worth it. doc brown has a rig with custom scales for 928's, custom software on a computer to do the math & really knows his stuff so it goes pretty fast once everything is setup.

iirc, for street cars about 20% is ok, for track cars less than 10% is the goal.

heinrich

I cannot tell if there is a difference between S4 and GT springs. My S4 springs (M474 Sport Suspension) on my 87 have two brown/orange stripes. I also have stock S4 springs elsewhere which have the same markings .... WTF?? Rears all have blue markings. Spring thicknesses between the S and M474 springs is the same.

Bill Ball

H'man:

I think there is only one spring type for all but Club Sport. M474 is sport shocks, not suspension. At one time I thought M474 was sport suspension and there may be some old erroneous posts floating around here that I wrote back then. I have that option on my S4, which meant the shocks were Boge Reds as opposed to Blue.

Jim bailey - 928 International

Theoreticaly the alignment would be checked after any load adjustment but as stated typically you will not move it much as you adjust balance.

heinrich

VERY interesting .... I recently had the 89 S4 5spd's suspension installed onto the 87 .... well, turns out for various reasons I had to re-do the work. While I was at it I installed new shocks too, as it turned out the 89's shocks were deader than the old facory sports on the 87 ... anyway I digress .. VERY INTERESTING, the front springs have GREEN paint markings. Rears have 2 blue stripes.

heinrich

Bill thanks for the update

Vilhuer

Paint markings in springs tell which version they are. There is one to three same color markings in each spring. They divide similar springs into three groups based on how strong they are. This was done to better match pairs of springs to be used in one end of each car. More equipment car has more likely its to have three line springs as they are strongest.

dom1102

I cannot for the life of me figure out how to make a new post in this forum (where is the new post button gone??)

Anyway, obviously this is an old post so hoping some of you are still using the forum. I have a 1988 928 s4. Its fitted with solid front wishbone bushes, bilstein coilovers and eibach springs (after the advise that given in this posting). The rear end has new standard bushes. The 4 wheel geometry (inc camber) is all set according to factory settings (when the car is on the deck). I have the ride height set quite low at the front (I like the way that looks). Its set to 1" tyre to arch gap (looking straight on from the side). Obvoisly the tie rods are not paralel to the wishbones but I am not sure if this is actual "bump steer". I am getting strange steering sensations over camber changes in the road surface, whereby the front wheels feel like they have a mind of thier own. At times I am compensating with the steering wheel to keep them pointing in the correct direction The car also follows thicker marking lines in the road wherby you can feel the wheel being forced to follow the direction of the road marking. And it does not just pull to one side, it will try to veer in both directions, sometimes one way directly followed by the other. I have had new steering rack bushes fitted and and the rack and all suspension and steering components have been checked for wear.

dom1102

....can anyone sugest why this is happening, there must be plenty of "lowered" 928's out there, do they all do this?? PS...tyre pessures are at factory reccomended settings.

heinrich

We don't lower our 928's as a rule. But sounds like worn tie rod ends

Rob Edwards

What front wheel offset are you running?

UKKid35

As Heinrich says, our cars don't like being slammed, even if it does look cool. As you said this changes the tie rod/wishbone geometry.

Sounds like you've spent a tidy sum already, so this must be quite frustrating. Have you actually lifted the car and checked for wear yourself? Could also be wear on the inner end of the tie rods, toe out, or uneven tyre wear.