dkash8

If I just want overall better handling on the streets in corners and tight/wide turns, and I don't want to buy new coilovers or any suspension hardware, then should I have both a rear and a front sway bar or just a rear one? Is anything good out there that is cheaper than the Neuspeed sway bar?

pink shrimp

This should be addressed to Eric Fletcher, not ErikS4, summon him!

chimchim101

Point one:
The purpose of sway bars is to mimic the effect of stiffer springs
with less ride harshness than one would experience by actually running
stiffer springs.

Under cornering, sway bars increase the perceived spring rate on the
loaded springs (the outside two springs in any given corner) while decreasing the
rate on the unloaded springs (the inside two springs in any given
corner).

This "transfer of energy" is best described as borrowing from the
inside spring rate to add to the outside spring rate. The effect while
cornering is the same as would be achieved by adding stiffer
liner-rate springs to begin with.

So when it comes to cornering, sway bars increase the stiffness
(spring
rate) of the loaded spring and have the same effect as would be
achieved by just running stiffer springs to begin with. Sway bar =
added stiffness (spring rate)

Point two:
Adding stiffness to one end of a car adds a higher percentage of the
available grip to the other end of the car. For example, we all add
coilovers packages from almost all of the manufacturers out there that
feature rear spring rates that are higher than the front spring rates
(opposite the factory setup which has stiffer front springs than
rear). The reason for the added rear stiffness is to add more grip to
the front wheels in an attempt to reduce understeer. As we all would
agree, our cars (and all passenger cars) understeer like crazy in
stock form.
Manufacturers set up
their cars this way for safety reasons. They don't want a car to swap
ends on the driver in an off ramp - they want the car to push in a
fairly straight line until enough speed is scrubbed to start turning
again. They achieve this by setting up cars with more stiffness at the
front than at the rear. They use larger front sway bars compared to
the rear and also use springs that are proportionally stiffer than the
rear (even more so than weight distribution alone would warrant).

When we add stiffer rear springs, the front turn-in is improved, more
throttle-steer is possible, and if enough rear spring is added,
lifting the throttle at cornering limits can result in the rear end
coming right around.

So the point here is that adding stiffness to one end of the car adds
more of the overall available grip to the other end of the car.

And therefore:
Removing a sway bar in effect, reduces the stiffness at that end of
the car which results in a proportionally increased stiffness at the
other end. By removing the front bar, which increases stiffness at the
back (in relation to the front), more front grip is added.

BUT:
Yeah, there will be more body roll. So adding stiffer springs all the
way around is a great idea. Adding stiffer springs, a stiff rear bar
and no front bar is a great idea unless you're already running rear
springs that are much much stiffer than the front ones.

The whole point is to maintain a nice ratio between the front and rear
with the rear being just enough stiffer than the front that you can
reduce or eliminate understeer without the rear end wanting to swap
with the front every time you trail brake into an off ramp.

In practice:
I don't want to pull an Eric Fletcher on you here - but let me tell
you where I'm coming from so you don't just assume I'm talking out of
my ***.

My S4 is set up with 500 lb springs all the way around, no front bar,
and the 21mm Neuspeed bar is on the rear on the stiffist setting. I
won the autocross at waterfest last year on a super-tight course with
the fastest time of all the cars and classes in the morning session by
over 2 seconds.

I autocrossed a Rabbit in the SCCA New England Region and won the
regional champiopnship two years in a row (before moving into road
racing) and also won two national tour events. Setup - TWO rear bars,
no front bar, 300 lb front springs, 350 lb rear springs.

I currently race a 1992 VW GTi 16V in SCCA road racing Imoroved
Touring class. It's a top 10 car but not a winning car. The only time
I win races is in the rain - but I always win in the rain :-) Setup is
400 lb front springs, 500 lb rear springs, no front bar, two rear
bars.

I've been nationally licensed road racing for 6 years now, and started
autocrossing many years before that. Unlike Eric Fletcher, you can
Google my name and come up with tons of winning race results as proof
of lack of bull****.

So enough bragging - I just want to make the point that I'm speaking
from experience and not out my *** when I say, getting rid of the
front bar will add front grip.

JohnKo

I might nit-pic some of the wording, but otherwise it's spot-on. Nice work.

ErikS4

the handling closer to neutral. Look into any rear bar that includes the sub-frame. I'm happy with my Neuspeed bar.

ErikS4

Thanks!

ErikS4

LOL! You're joking right!