jemitchell@compuserve.com writes:
<<
>However, unlike with corner
> weighting you have no effective way to raise or lower one end of the car
> equally with adj swaybar endlinks to address front/rear balance.
If you're saying what I think you're saying, there's a mistake here: a
car's total F/R and L/R weight distribution cannot be changed by any
suspension adjustment. That's a function only of the CG location
relative to the wheels.>>
Actually it can be done, but it's a very minor fine tuning adjustment at best
and more often then not it's not practical. I never really should have
mentioned it per-say because of that. I just wanted to point out that this
was the only minor difference between the two adj methods. What happens
(spring height adj only) is that the CG/chassis can be shifted slightly
relative to the wheel base with an angular attitude change. It often takes
extreme changes to get any kind of significant change, so it's really not
practical. I seem to recall this phenomenom being demonstrated in a
Grassroots Motorsport article a year or two ago regarding corner weighting
adjustments involving a Honda track car.
<<
> Now if the case of both corners on the same side of the car having higher
> weights than the other side, you're *potentially* SOL in the Stock class...
Well, you're SOL in that case even if you've got fully adjustable
coilovers. My car is approximately 54/46 L/R with driver, and no amount
of adjustment will ever change that. I can, however, make certain that
the weight on each wheel correctly reflects the CG location. The target
is the same L/R distribution at the front and rear as the total L/R. Or,
equivalently, the same F/R distribution on each side of the car as the
total F/R. That's the best you can do. The total weight on any two
adjacent wheels won't change.>>
You misunderstood me, but it's my fault for not being more specific. What
you're saying is correct for practical purposes. All I meant is that you
don't have any adjustment but at the front, which limits how you can
manipulate in a fine tuning manner within the specific weight/height
parameters, just like having coilovers only on one end of the car. Remember
I stated that the exact weight conditions that existed would determine what
could be achieved in the end result.
<<
> In this situation if you try to balance the front corners using the adj
> front endlinks you'll also create more bias to heavier side of the rear
> corner in the process.
Any time you reduce the weight at one corner via adjustment, you also
reduce the weight at the diagonally opposite corner. This has the effect
of increasing the weight on the two remaining corners. It doesn't matter
if you perform the adjustment with swaybar end links or spring perches,
the effect on corner weights is the same.
>>
That's exactly what I said in my example, but let me try to clarify it
better, unfortunately with details. In my example I said the weight on one
side was higher than the other, let's say the left front is 700lb, the right
front is 600 lb, the left rear is 600 lb and the right rear is 500 lb. Our
only adjustment is the front bar end links. this means the front/rear
balance is 1300f/1100r, and the left/right balance is 1300L/1100R For the
sake of the argument let's say the bar dia, end link adj. range, etc, is
capable of doing whatever we want in our example. That's not always the case
in reality) We can balance the front corners by adjusting the endlinks to
yield left front and right front are 650 lb each. As you stated previously,
and what I intended but failed to make clear, the total front weight is still
1300 lb and the rear weight must also only be the original 1100 lb, but the
left/right rear corner weights will change to equate to the original L/R
balance, in this case the left rear will increase from 600 lb to 650 lb and
the right rear will decrease from 500 lb to 450 lb, still a total of 1100 lb
rear weight, total of 1300 lb left weight, and a total of 1100 lb right
weight. That's exactly what my detail-less example said; you could
potentially balance the front corners to be equal (again depending on
specifics), but in the process you'd bias the heavy rear corner even further
in the process. I further added that this unconventional result might
actually be desirable if there were other methods to compensate the uneven
rear corner weights. In this particular example we ended up with 3 corners
at 650 lb and the right rear at 450 lb.
Now there are very specific reasons it would be preferred to have adjustments
at all 4 corners rather than at two on one end, but I've written too much for
one post as it is.
M Sipe
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