Songzzz

This should be quite a common setup for street use:

- 951 M030 Koni Adj Yellows
(No rear spring and need to be removed for adjustment)
- Std M030 front spring.
- 968 M030 Swaybars front and rear.
- Stock 86'951 Torsion Bars.
- 17" Cup1 wheels (225/255 tyres).

Anyone with similar setup, please advise your shock vs sway bar settings.

I set both the front & rear shocks at the mid-point and R swaybar at the mid-point too. With this, I have too much rear squat..

To solve the problem without going the larger TB route, can I add some helper springs instead?

By the way, what's the stock front spring rate? 170#?

Rally Guy

When you say "squat", do you mean the rear of the car is sitting too low? (Ie. corner weights are way off?) or do you mean you're getting way too much "compression" of the rear suspension under weight transfer during acceleration?


RK

J Chen

Hi Songzzz,
I'm running Leda coil overs all round. Fronts are 300lbs rears
are 400lbs. The fronts are little stiff for the roads here. Thinking
of going down to 200-220lbs. Regards to your squatting, I presume
you're talking about hard acceleration. Helper springs may help a little
but do some research. I remember reading somewhere that if the
springs & T bars aren't set-up in sync high oscillation will occur.
FYI, with the 400lbs rears that I'm using, theres still some squatting
under heavy acceleration

keith

You cannot get rid of squat and maintain decent handling with the stock spring rates. These cars are way undersprung, IMO.

Songzzz

Rally Guy: yes.. "way too much "compression" of the rear suspension under weight transfer during acceleration" is what I meant.

J Chen: Rears 400lbs.. with your TBar deleted? Where did you get the Leda stuff?

Guys,there is way too much compression (squat) at the rear, every launch is like a fat scrambler trying to wheelie...

Just trying to figure if there's a way to "counter" squat.

Jon Moeller

I think the only effective solution is to increase the rear spring rate. You could crank up the bound on the rear shocks, but that would most likely make the rear skittish under conditions other than acceleration.

Upping the front spring rate without a similiar raise in rate at the rear is going to cause more squat. I would look into KLA's solution with the rear coil-over shocks that are run with the t-bars.
-J

J Chen

Hi Songzzz,
Got the Ledas direct from U.K. You've got to realize one
thing. You've got to draw the line between road comfort
& handling. Theres no two ways about it. BTW Koni gas
shocks are a no no for our roads here. After using my
set-up for 2 yrs plus, I think 200-230 lbs fronts with
300-350 lbs rear would be a good compromise. If you
get helper springs, you would still have to re-index the
T bar. It's got to do with preloading both the springs to
get it in sync. Generally, when you go stiffer springs you
should not upgrade the sway bar to stiffer specs cause
that will induce more understeer at the limit which you
would then have to stiffen the rear to neutralise or balance
it out. You may be able to adjust the car to reach a stage
of neutral slight at the limit but that does not mean that
you have increase traction. For all you know, you could
be pulling less G's in Turns than the M030 set-up. Are you
using the M030 springs & T bars ? If not maybe you should
it a try.

Songzzz

So, we are trying to stiffen up the rears right?

Let's just say, we adjust the rear shocks up to max. hard and set rear-sway bar to stiffest position with the front at 50% hard... will this do?

KLA rear coil-over seems to be a stright-forward solution.

Where to buy parts for the rear "helper spring" conversion?

Songzzz

I am a suspension idiot. Pardon my ignorance.

These suspension kits don't come cheap.

J Chen, maybe we can some local factory to custom a set of shock/spring combo for us?

Jon Moeller

Songzzz,
Roughly, you're looking at ~$2100 for the full Leda setup. Definitely pricey.

The compromise you suggest with the rear sways and rear shocks is not ideal, and won't provide the desired result. Quick explanation:

Sways provide cornering balance to the car, and help control side-side weight transfer. They help dictate over/under steer.

Shocks/Struts control how fast movement of a given suspension point occurs (4 wheels on a car).

Springs determine the amount of movement that occurs at a given point.

Thus, the rear sway has no effect on squat during acceleration, and raising the rear shock bound will slow the rate of squat. I think the side-effect of this stiffening is that the rear will be very skittish at higher speeds.

I'm not a guru, so others can feel free to comment on it, but this is my understanding to this point. I agree that these cars are grossly undersprung, I'm running 350# fr and 550# rr springs with the Ledas on my Turbo, which will serve for street/track duty.
-J

J Chen

Hey Jon,
If I use your spring rate set-up. I'll proberbly
loose all my teeth. Running 400 for the rears
is o.k but maybe I'll try 350lbs. Fronts 300lbs
is a little stiff. A good compromise would be
about 220 to 250 lbs for street especially for
our road conditions here.

Ah Songzz, Jon has given a pretty good outline
on the suspension subject. The thing with Koni
shocks if I'm not mistaken is that you adjust for
bound but no rebound. For road shocks I feel
that it's better to have adjustment for rebound
instead. Let the spring do the other half of the
work. Remember, the real purpose of the shock
or damper is to control the oscillation of the wheels,
springs when the car travels over an undulation.
Same for brakes. Most people would think that it's
the brakes that stops the car. Which is not true.
Also by going bigger brakes does not necessarily
equals better braking.
I'll try to catch up with you soon. Lets see what
can to done.

Z-man

For street use, I think the stock setup that you have is about as good as you can get.

I would crank up the rear Koni's one notch: that may help with the 'squat' issues you have.

But again, for the street, if you go too firm, you'll be compromizing your ride quality.

If you have understeering issues, you can a) go back to your stock front sway bar or b) change your rear sway to full firm.

BTW: Adjust only one thing at a time, that way you'll know how each change effects your handling.

Just my $0.42,
-Z-man.

Jason @ Paragon Products

The adjustment for single adjustable Koni's is for rebound. Only with double adjustable units will you gain bump (aka compression) adjustment.