> 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?
They also change the handling balance of the car. A thicker than stock rear
sway bar will try to push up on the inside wheel, limiting its traction,
giving you more oversteer. In my Probe GT, I've lifted the rear inside
wheel under hard cornering/braking due to the stiff sway bar (22mm vs. stock
12mm).
> Suspension springs: Their major function is to support the weight of the
> vehicle and also control body lean while cornering. Right?
I read on some racing site (so I don't know how good it is) that
theoretically, you want the stiffest springs possible to keep geometry in
check. But, since we don't live in a perfectly smooth world, you need
springs that keep the tire in contact with the pavement. So, you might want
600lb springs on a smooth track, but 300lb springs on a bumpy track.
They do of course support the weight of the car and control body lean.
Supposedly, if you have stiffer springs on the rear, the rear sway bar
doesn't have to work as hard. I read from some site that to control roll,
you must have sway bars because it would take some crazy stiff springs to
equal the effect of a sway bar.
> 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?
Yep... that sounds good to me.
> 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 springs would help keep the car flatter, but like above, nothing beats a
sway bar.
> 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.
This is also my complaint about the Intrax springs I bought for my PGT. I
didn't want to void the Tokico warranty by using Ground Control's, so I went
the next feasible route. The only thing is the Intrax springs aren't that
much stiffer. Something discussed widely on the Probe mailing lists was if
you have a height adjustable suspension (ie GC), when you change the height,
you change the overall spring rate if you have progressive bump stops.
> 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?
It would probably be a good place to start. Seems like most autox'ers I've
seen have been using spring rates in the 400-500 range. If you're getting
too much understeer or oversteer, that's when you can change sway bars.
It's probably a good idea to talk to some Neon guys to see how they set up
their cars. The Probe GT comes OEM with a 25.4mm front bar, 12mm rear,
190f/145r springs. That's with ~900lb/front wheel ~500lb/rear wheel. I'm
using a 22mm rear sway bar now, and with stock springs and struts, I could
get a lot of oversteer. With Intrax springs and Tokico struts on 3f/5r its
fairly balanced. I want to get more negative camber up front though so I
can stiffen up the front struts.
> 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 would assume so for the first part. If you have access to a pyrometer,
that would be good. I want to figure out a way to check tire temps (maybe
use a chemistry lab thermo-probe thing?) since that's usually the best way.
I've thought about loading IR film in my camera too.
Brian
--
Brian Berryhill
http://www.angelfire.com/ms/brianberryhill/
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