Plan to Improve Handling

[SteveCo]

I thought that understeer/push was addressed by stiffening the front? Overseer can be reduced by stiffening the rear.

Actually the other way around - stiffening the front or back is going to increase understeer and oversteer respectively.

 

[MerlintheMad]

I thought that understeer/push was addressed by stiffening the front? Oversteer can be reduced by stiffening the rear.

Actually the other way around - stiffening the front or back is going to increase understeer and oversteer respectively.

Are you sure about how you said that? I've messed this up so many times in writing while understanding what I mean.

I've had oversteer, and stiffening the rear bar has reduced (so far eliminated) that; even on the soft setting (the stiffness above OE is 76%).

My understanding is that if I put the rear Eibach on stiff, the degree of oversteer will be further reduced, and I may experience understeer instead; which would require (if I wanted to keep the rear bar on stiff) the addition of the front bar; on soft it may be enough to get rid of the understeer; but if not, then I'd need to set the front bar on stiff as well.

 

[SteveCo]

Are you sure about how you said that? I've messed this up so many times in writing while understanding what I mean.

I've had oversteer, and stiffening the rear bar has reduced (so far eliminated) that; even on the soft setting (the stiffness above OE is 76%).

My understanding is that if I put the rear Eibach on stiff, the degree of oversteer will be further reduced, and I may experience understeer instead; which would require (if I wanted to keep the rear bar on stiff) the addition of the front bar; on soft it may be enough to get rid of the understeer; but if not, then I'd need to set the front bar on stiff as well.

Perhaps you have the two mixed up - oversteer is when the rear end swings out on a turn, understeer is when the front end plows ahead instead of turning. Car manufacturers generally do not sell cars that have oversteer tendencies - that's potentially a much more dangerous behavior for the general public than dealing with understeer.

Lots of explanations of the physics involved online - here's one of the first articles that popped up on a quick search.

Anti-Roll Bars: How to Choose the Right Sway Bar for Your Driving Style

This an excerpt from it, regarding AWD cars:

All Wheel Drive (AWD) Cars: To put it simply, if you drive an all wheel drive car that understeers, install a stiffer rear sway bar. If you drive an all wheel drive car that oversteers, install a stiffer front sway bar. All wheel drive vehicles all handle a little bit differently, this means that choosing the right combination of sway bars will depend on how your specific vehicle behaves.

 

[MerlintheMad]

Perhaps you have the two mixed up -

Not now. But back in January, before I even got my rear bar in, I did; and @NS_Stinger reciprocated; and you didn't catch either one of us out!
Eibach Rear Sway Bar Impressions
Eibach Rear Sway Bar Impressions

Anyway, despite my reading of "oversteer" and "understeer" bassendackwards I still managed to improve the handling of my car like I wanted. God looks after his own! (and corrects their ignorance by degrees, according to his own inscrutable timing)

Now, how in the devil am I going to reprogram my poor brain? I've got "stiffer in back reduces oversteer" crammed in there!

It's even counterintuitive. It seems to me that if your car plows for the outer edge, the last thing you'd want/need is a more planted rear end: instead, wouldn't you want the back end to start to come out, and promote pointing the nose in the right direction?! So, I think I'm cooked until something clicks and sorts this out for me.

It's very, very weird, now, to reread that thread and all the verbiage I expended talking about this while completely reversing the two terms in my mind.

Oh, well.

Here's a possible fix (to reprogramming my brain): oversteer is a front feeling, so get a front bar upgrade. Understeer is the opposite, so get a rear bar upgrade. Heh!? Trouble is, if I start at this in the reverse order - talking about understeer first - that is also a front end feeling. I'll just have to remember that last fall I experienced oversteer for the first time in my Stinger. And that is what I wanted to get rid of. I got the "wrong" bar for that; but the right bar for reducing the unsettled back end. I haven't ever really talked about understeer because my car has never done that (even with an upgrade that has the potential to induce understeer where there hasn't been any). So I just have to remember that the feeling I have experienced is answered with a stiffer front end.

At least now I know that if I experience oversteer again, the answer is NOT to put the Eibach rear bar on "stiff!"

 

[WildBill]

 

[MerlintheMad]

LOL! That will help. Thanks!

 

[MerlintheMad]

And I see that I am not alone.