> Howdy all. Hope all y'all had as much fun at nationals as I did, despite
my
> poor (albeit not as bad as last year) finish.
>
> Anyway, I've got a few suspension questions and would appreciate some help
> from you all.
>
> Sway bars: Their basic function is to control body lean by transferring
> some of the "lift" or "dive" action of one side of the car to the other.
> Right?
>
> Suspension springs: Their major function is to support the weight of the
> vehicle and also control body lean while cornering. Right?
>
> Negative camber: Used to try to keep the tire's contact patch as flat as
> possible while cornering due to under effective springs/sway bars. Right?
Negative camber also helps to offset the deflection of the tire as it
deflects
and tries to roll over onto the shoulder.
>
> So, if I were to install stiffer rate springs on my car, a Neon, would I
> then not need as stiff of sway bars since the stiffer springs would help
> keep the car flatter in the corners?
>
> The reason that I'm asking is that I'm now shopping for some suspension
> goodies so I can build my DS Neon into a STS car for next season and am
> attempting to put together a list of items that will complement each other
> nicely. I'd hate to go from the factory 150 lb/in front and 120 lb/in rear
> springs to 450 lb/in F and 500 lb/in R coil-over springs and install
stiffer
> F&R sway bars only to find it a totally unbalanced package.
As I recall a rule of thumb is to have 20-50% of your total roll
stiffness from sway bars. For a FWD car, most people run a lower
percentage of sway bar on the front than the back. This tends to help
inside tire wheelspin since the swaybar tries to lift the inside wheel.
Remember, both sides are connected together by the bar, so when
you push down on the outside, the inside tends to pull up.
The very stiff rear springs will help a bunch to plant that inside tire, but
they will ride VERY rough on the street. At the beginning of the year
I had 550's all the way around on my car ('95 FWD Talon for those
that don't know). The stiff 550's on the back helped a bunch, but were
almost intolerable on the street. Since I put in the Quiafe LSD, I've
since went back to 450's on the rear. I have a stock front bar and
a 1" rear bar (stock was about .6").
Also, if the car lifts the inside rear wheel, then the balance of the car
will not be greatly effected by changing the rear stiffness. This has
been my experience with my car. This makes sense. When you stiffen
the rear of the car, you transfer more weight off the rear inside tire.
Once all the weight is transferred off that tire, the rest must come from
the inside front tire. Remember, no matter what f/r stiffness you run, for
a given center of gravity height, car width, and G-level, the same amount
of weight is always transferred. Your just changing where it comes from.
Either front or rear inside tires.
There are some good books on this stuff. I think Dennis Grant has a bunch
of them listed on his site.
http://www.wincom.net/trog/stu/books.html
>
> So, if I put these stiffer springs on (rates recommended by Pro-Parts)
might
> I be able to utilize my current sway bars (20mm F and 16mm R) which
> currently give the car a nice balanced feel rather then going out and
buying
> the fattest sway bars available?
>
> Also, if the stiffer springs help keep the car flatter through the turns
and
> consequently not change the camber as much, would I be able to get away
with
> slightly less static camber than I'm currently running (about -1.7 degrees
> per side F and -0.5 degrees R)? Or should I use tire wear patterns or
> surface temps to determine the best camber settings?
>
I'm not sure how much camber is ideal for most street tires.
Most say it's 2-3 degrees negative for R-tires, probably similar
for street tires.
Anyone have opinions on this? (Kinda a dumb question,
everyone has opinions on this list don't they! ;-) )
Dave G.
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