I'm getting some PSS-9s soon, and asked the shop about getting a corner balance done.

It's a very reputable and highly regarded shop, but they say they don't corner balance street cars. Now, I have zero technical background in this, so I don't want to waste the reps time asking why and saying I want it, so can anybody validate or refute that?

 

The only reason I could believe they’d say no is because many street cars aren’t adjustable. The PSS9’s will allow it to be totally adjustable. The only other problem would be if you have non adjustable anti roll bar drop links. In that case it very hard to take the preload out. With that in mind, tell him, YES you want it and if he still says they don't do street cars...tell him it's a race car.

 

I agree completely with Cary (Cary is suspension Guru) and that is one of the big pluses of getting coilovers, you can corner balance. Just do it.

 

Can a Porsche dealer corner balance a car? If not, can anyone recommend a good shop in the DFW area? Anyone have any Porsche experience with Autoscope in Plano? I know they do a lot of BMW work and they are supposed to be REALLY good. They do Porsches too, I've just never talked to anyone with a Porsche that's had work done there. Not sure if they specialize in just BMWs or if they are equally as good with Porsches...

 

Cary, I am not worthy to add to this thread but I do have a question. Corner balance with me in or out of the car and if I weigh less than 200 # and the car is 3200 # does it matter? I would add for the uninformed that this means weight of front right + left rear = right rear + left front = corner balance. Some tracks like Roebling Road in Savannah, GA have weight scales and will print the weights of the four corners on a cash register receipt for free.

 

I would do it with you in, and with you out. The corner weights
should be equal under both conditions, because they are a
measure of how balanced the springs and dimensions are.
Joe

 

Do a search for corner balance in this group. I'm sure I posted
a longer bit on it... The point is that someone could mis-install
new suspension parts and then do corner weights unloaded,
and then dial in a second equally wrong adjustment that made
the corner weights work out OK with the car unloaded, but the
minute you sat in the car you might have serious corner weight
imbalance. For instance if one spring happened to be weaker
than it's counterpart, the installer could simply dial in more
preload on that corner to make everything balance as the car
sat there, but that corner would still travel more per unit ofnew
load than the others, so the car isn't how you'd like it. You'd
discover that the instant you did a second set of corner weights
with 200lbs in the driver seat or in the trunk etc. (Any two
significantly different loadings are enough to discern a problem.
The only way you can really know that everything is really set up
correctly with good matching parts is to do corner weights under
two loading conditions.
Joe

 

It's a common misconception that 'installing coil-overs allows
you to corner-weight'. Installing any adjustable suspension
component allows you to adjust, but if your corner weights
are off because the frame is tweaked, or because the welder
mounted one upper shock mounting point off, all the adjustments
to suspesnsion parts can do is to mask the real problem at
one suspension loading.
The ideal thing to do is to test the springs individually, off the
car to make sure they are as close as possible in length and
strength. Then install them on the coiloves, and ensure they are
compressed to the exact same preload/length so the units are
matched. Then install them on the car and take corner weights
with the sway bars detached at one end so they don't pollute
the reading. This should give you a good idea whether your
chassis and mounting geometry is straight. Then hook up the
sway bars. Note that sway bar ends can be mistightened to
dial in some side-to-side preload, which will totally screw up
the corner weight measurement, so most folks do loosen one
end before measurements. Heck! *Make sure your tire pressures
and wear levels match! If one tire is under-inflated it's just like
having a weaker spring on that end.
You can *do* corner weights without any adjustable suspension...
Stock car racing with big'ol American tail-happy sedans is a one-
way affair so it's easy to run a wider diameter tire on the rear
outside corner to purposely skew the corner weights to make the
car more balanced for the turns. Needless to say if they decided
to run the track the other way around the car would be laughable.
Joe