Eibach F/R Swaybar Review!

[ZyroXZ2]

Yea, it's another one! But guaranteed to be more detailed than you could have ever imagined because I'm one of the handful of people who *GASP* installed them myself! Got them from Nick at Khartunerz as they had JUST come back in stock and I've been looking around for them. I'm also a RWD GT, so no electronic suspension control (I hate that kind of stuff anyway, lol).

First off, if you do plan to do this yourself, set aside some significant time for the rear swaybar. If I had to do it now, it would take me relatively no time at all. But up until I got it, I was sitting there with a pile of u-joints, various 1/4" or 1/2" socket wrenches and sockets, a breaker bar socket end, ratcheting wrenches, 15 degree and 45 degree box wrenches, you name it. It was all about sitting there until I found the right combination to be able to turn just that 1"-2" to either loosen or tighten for the new bracket. It's entirely doable, but I will warn you that you need some decent finger grip and strength because you'll rarely be afforded the luxury of a full-hand grip on the handle of anything In addition, Eibach used aluminum brackets. As you'll see in the pics below, in order to afford the strength of a steel bracket it has reinforcing "walls" that make it impossible to use a wrench. Thanks, Eibach.

Second, and by far the most important point, follows after you see the pics:

Front Swaybar on Firm:


Rear Swaybar Bracket:


Rear swaybar on Firm and Centered Bracket View:


That last pic brings me to the most important thing I noticed about these swaybars. The Eibach bracket holes are slotted which allows the bracket and thus swaybar to actually be mounted in slightly different positions which can affect preload of the swaybar and/or difference in handling characters between left and right turns. I took the time to make sure that the bolt (and thus bracket) was perfectly centered in the slots on both swaybars, but there's a full inch of play. That play was enough for me to slide the bar around and see how it changes the angle of the endlink and thus could affect the load angle. Since both are free to slide around, it's possible to have a full inch forward on one side, and a full inch backward on the other which in my fiddling sat the bar crooked across the vehicle rather than straight across. This concerns me greatly: I think Eibach engineers didn't want to take the time to ensure bracket precision and just used general slots to minimize fitment issues figuring most people won't notice the difference anyway. Leading into my final thoughts on them is another point of contention: the factory swaybars actually lock into the brackets, thus resisting rotation of the swaybar. The Eibachs are free to rotate. This has a bearing on suspension bounce when both wheels go up and down together: the factory one actually slightly dampens this motion while the Eibachs do not.

So how does it feel you ask? Absolutely great. Not only does it tighten up road feel and handling response, but also firms up the ride over mildly bumpy roads. I almost regret having ordered it as part of a "kit" (I'm putting in sport springs this weekend, so stay tuned on that, too!) as I feel people who just want a slightly firmer ride and better cornering need only order the Eibach swaybars, put them on firm, et voila. I live near a very winding road, and I could easily push another 5 MPH on the tight, blind curves without even feeling like I found the limit, yet. I could even ease into the gas a little, hinting at oversteer but instead letting me accelerate through the S curves. This hinted that it had even more room in it than before to go a little faster! But all isn't perfect. I've noticed an increased "shimmy" behavior when going over speed bumps at a slight angle, or that steep driveways can no longer be "rushed" as the car basically feels like it's getting popped up into the air side-to-side. I now have to go over speed bumps and steep driveways slower than before because the car has become less compliant. This could be mitigated by setting the bars on "soft", but that would probably defeat the purpose and eliminate the firmer ride afforded by the firm setting. Additionally, I went into a driveway that was a bit too steep at my usual speed, and my head hit the B pillar because the car basically got rocked like a cradle I believe that the factory swaybars add a bit of mild but constant dampening due to their locked position, and this explains why there's a sort of "pop up" with the Eibachs when going over anything steep before the dampers can properly dampen the motion.

My final notes, however, are that mileage may vary because of those brackets. I also think that this could have a bearing on endlink longevity based on the angle of load. You might think that the angle difference is so small it doesn't matter, but solid swaybars put more load on the endlinks, and this IS a 4000lb car we're talking about... If/when you get a chance to take your wheels off, check the bracket position: if anything, you'll want them even from side to side. I have mine perfectly centered, and that could be affecting my experience compared to others, but I'd check it anyway. I highly doubt a shop or a mechanic being paid to do this will take the time to perfectly center the brackets before tightening them down, and it's the reason I like to do things myself because I'll take just that little extra time to do something "right". It could explain why some have a weird feel after getting the swaybars installed, so check those brackets!

EDIT:

INSTALLATION TIP - If you are doing this on the ground like I did, have a 3rd jack or use the jack from the trunk. When you unload the suspension, the rear swaybar endlinks may be locked in place due to the tension of the pull. Don't risk damaging them by trying to knock them out: just place the 3rd jack under the arm and gently jack the entire assembly up until the tierod is loose and simply slides right out.

EDIT 2: Clarity.

 

[MerlintheMad]

the factory swaybars actually lock into the brackets, thus resisting rotation of the swaybar. The Eibachs are free to rotate. This has a bearing on suspension bounce when both wheels go up and down together: the factory one actually slightly dampens this motion while the Eibachs do not.

Oh my, this is directly addressing the earlier discussion about "fixed" sway bars not working like sway bars are supposed to. So you have confirmed that the OE rear bar is "fixed". And this makes me return to my theory that Kia designed the handling around a "fudge" of what a genuine sway bar usually does, by using a less heavy bar but made stiffer "artificially" by locking it in place. It works (for most people).

But this does pose the question: why rear end "bounce" would be resisted more by the locked design of the OE sway bar; while everyone who replaces it with the rotating Eibach asserts (groupthink subjective reasoning?) that it makes the rear end more "planted" and eliminates or greatly reduces the "bounce/float" of the OE setup.

 

[AV8R]

Yea, it's another one! But guaranteed to be more detailed than you could have ever imagined because I'm one of the handful of people who *GASP* installed them myself! Got them from Nick at Khartunerz as they had JUST come back in stock and I've been looking around for them. I'm also a RWD GT, so no electronic suspension control (I hate that kind of stuff anyway, lol).

First off, if you do plan to do this yourself, set aside some significant time for the rear swaybar. If I had to do it now, it would take me relatively no time at all. But up until I got it, I was sitting there with a pile of u-joints, various 1/4" or 1/2" socket wrenches and sockets, a breaker bar socket end, ratcheting wrenches, 15 degree and 45 degree box wrenches, you name it. It was all about sitting there until I found the right combination to be able to turn just that 1"-2" to either loosen or tighten for the new bracket. It's entirely doable, but I will warn you that you need some decent finger grip and strength because you'll rarely be afforded the luxury of a full-hand grip on the handle of anything In addition, Eibach used aluminum brackets. As you'll see in the pics below, in order to afford the strength of a steel bracket it has reinforcing "walls" that make it impossible to use a wrench. Thanks, Eibach.

Second, and by far the most important point, follows after you see the pics:

Front Swaybar on Firm:


Rear Swaybar Bracket:


Rear swaybar on Firm and Centered Bracket View:


That last pic brings me to the most important thing I noticed about these swaybars. The Eibach bracket holes are slotted which allows the bracket and thus swaybar to actually be mounted in slightly different positions which can affect preload of the swaybar and/or difference in handling characters between left and right turns. I took the time to make sure that the bolt (and thus bracket) was perfectly centered in the slots on both swaybars, but there's a full inch of play. That play was enough for me to slide the bar around and see how it changes the angle of the endlink and thus could affect the load angle. Since both are free to slide around, it's possible to have a full inch forward on one side, and a full inch backward on the other which in my fiddling sat the bar crooked across the vehicle rather than straight across. This concerns me greatly: I think Eibach engineers didn't want to take the time to ensure bracket precision and just used general slots to minimize fitment issues figuring most people won't notice the difference anyway. Leading into my final thoughts on them is another point of contention: the factory swaybars actually lock into the brackets, thus resisting rotation of the swaybar. The Eibachs are free to rotate. This has a bearing on suspension bounce when both wheels go up and down together: the factory one actually slightly dampens this motion while the Eibachs do not.

So how does it feel you ask? Absolutely great. Not only does it tighten up road feel and handling response, but also firms up the ride over mildly bumpy roads. I almost regret having ordered it as part of a "kit" (I'm putting in sport springs this weekend, so stay tuned on that, too!) as I feel people who just want a slightly firmer ride and better cornering need only order the Eibach swaybars, put them on firm, et voila. I live near a very winding road, and I could easily push another 5 MPH on the tight, blind curves without even feeling like I found the limit, yet. I could even ease into the gas a little, hinting at oversteer but instead letting me accelerate through the S curves. This hinted that it had even more room in it than before to go a little faster! But all isn't perfect. I've noticed an increased "shimmy" behavior when going over speed bumps at a slight angle, or that steep driveways can no longer be "rushed" as the car basically feels like it's getting popped up into the air side-to-side. I now have to go over speed bumps and steep driveways slower than before because the car has become less compliant. This could be mitigated by setting the bars on "soft", but that would probably defeat the purpose and eliminate the firmer ride afforded by the firm setting. Additionally, I went into a driveway that was a bit too steep at my usual speed, and my head hit the B pillar because the car basically got rocked like a cradle I believe that the factory swaybars add a bit of mild but constant dampening due to their locked position, and this explains why there's a sort of "pop up" when going over anything steep before the dampers can properly dampen the motion.

My final notes, however, are that mileage may vary because of those brackets. I also think that this could have a bearing on endlink longevity based on the angle of load. You might think that the angle difference is so small it doesn't matter, but solid swaybars put more load on the endlinks, and this IS a 4000lb car we're talking about... If/when you get a chance to take your wheels off, check the bracket position: if anything, you'll want them even from side to side. I have mine perfectly centered, and that could be affecting my experience compared to others, but I'd check it anyway. I highly doubt a shop or a mechanic being paid to do this will take the time to perfectly center the brackets before tightening them down, and it's the reason I like to do things myself because I'll take just that little extra time to do something "right". It could explain why some have a weird feel after getting the swaybars installed, so check those brackets!

Informative review, are you going to change the end links to heavier ones as well?

 

[ZyroXZ2]

Oh my, this is directly addressing the earlier discussion about "fixed" sway bars not working like sway bars are supposed to. So you have confirmed that the OE rear bar is "fixed". And this makes me return to my theory that Kia designed the handling around a "fudge" of what a genuine sway bar usually does, by using a less heavy bar but made stiffer "artificially" by locking it in place. It works (for most people).

But this does pose the question: why rear end "bounce" would be resisted more by the locked design of the OE sway bar; while everyone who replaces it with the rotating Eibach asserts (groupthink subjective reasoning?) that it makes the rear end more "planted" and eliminates or greatly reduces the "bounce/float" of the OE setup.

Oh this one's an easy answer: it doesn't. Cornering is a left-right differential weight transfer, and for those who don't understand cornering (not in a mean way, most people don't), they don't know how to manage the throttle to control the rear end of the car. In an effort to balance ride and handling, the rear swaybar itself has more play. The hop comes from a one-wheel lift, essentially. Without "loading" the rear with a mild amount of throttle, the car is mildly understeering which exacerbates a rear, one-wheel lift and you get the hop because the car actually wants to bring the rear around. Increasing oversteer in handling characteristics can also mitigate this, but comes with the increased risk of idiots spinning out (and thus most non-super/hypercar aim towards mild understeer even in a RWD or 50/50 weight split design). When a firm swaybar is used, the same hop could probably be achieved over a larger bump, but a small one sees the one wheel stay planted on the ground. This gives the illusion of eliminating the problem, but there really wasn't a problem to begin with. I guarantee with 100% certainty I could have gotten into any of the Stingers of people complaining about the hop, go over the same bump during cornering and keep the rear from hopping, lol

Informative review, are you going to change the end links to heavier ones as well?

Yea, when Moog or some other company releases some aftermarket OE replacements (non-adjustable). The Whitelink ones are a total ripoff and wayyyy overpriced. They allow for pre-load adjustment (so perhaps someone could set the Eibachs to the soft setting and tune it with the Whitelinks so that it's somewhere in-between the soft and firm setting), but that's just not worth that amount of coin. I put upgraded Moog endlinks on my old car, as they were much beefier. They only cost 10% more than factory ones, lol

 

[MerlintheMad]

I guarantee with 100% certainty I could have gotten into any of the Stingers of people complaining about the hop, go over the same bump during cornering and keep the rear from hopping, lol

This is the most intriguing thing to me: how to judge gas input to pull through a continuous turn, like a cloverleaf/skidpad. I've watched videos of it being done and it is unlearned lore to me. I guess I'd have to be in the car and watch/feel it at work, then try it. I don't think I'm ever going to experience this on my own: unless I push the Stinger too far and power-drift out of the corner screaming all the way, i.e. get lucky through natural luck/talent!

 

[Ruturaj]

Thank you for sharing. Very informative post. I am putting sways on this Friday (you might already know), since mine is 2019, I would ask installer to check if sways on mine are also locked. I think they would be.

 

[Tobstertx3]

How long did it take you?

 

[ZyroXZ2]

This is the most intriguing thing to me: how to judge gas input to pull through a continuous turn, like a cloverleaf/skidpad. I've watched videos of it being done and it is unlearned lore to me. I guess I'd have to be in the car and watch/feel it at work, then try it. I don't think I'm ever going to experience this on my own: unless I push the Stinger too far and power-drift out of the corner screaming all the way, i.e. get lucky through natural luck/talent!

Well, it's simpler than that: the reason a car aims for 50/50 is because with constant speed, the car will maintain neutral balance through a corner. A car that understeers may need a little MORE throttle to maintain neutral balance, and a car that oversteers may need LESS throttle to maintain neutral balance. That's actually all it really is, lol

 

[ZyroXZ2]

Thank you for sharing. Very informative post. I am putting sways on this Friday (you might already know), since mine is 2019, I would ask installer to check if sways on mine are also locked. I think they would be.

Your installer should be giving you back your factory ones, you can then check for yourself, lol

How long did it take you?

About 15 minutes. Easiest thing I've ever installed.

- No Stinger Owner Ever

Honestly, I didn't keep accurate track since I also took the time to clean my calipers off, check tire wear, and analyze my approach for the sport springs I'm putting in this weekend. If I had to focus just on the swaybar installation at its core, about 30 minutes for the front, about 2 hours for the rear. I could probably do the rear in 30-45 minutes now, too, though since I know exactly how to go about it, lol

 

[MerlintheMad]

Well, it's simpler than that: the reason a car aims for 50/50 is because with constant speed, the car will maintain neutral balance through a corner. A car that understeers may need a little MORE throttle to maintain neutral balance, and a car that oversteers may need LESS throttle to maintain neutral balance. That's actually all it really is, lol

Right. 50/50 what? Power to wheels or weight distribution? Yeah, people in my position will ask the most obvious, basic questions?

And if it's weight, the Stinger is pretty darn close. If it's power to wheels, RWD is 100% rear; AWD can be 50% but Sport puts 80% back there. What is the possible advantage of that?

 

[NICK_KHAR]

Thanks for the support! Glad you got them on and installed!

 

[Manaz]

Right. 50/50 what? Power to wheels or weight distribution? Yeah, people in my position will ask the most obvious, basic questions?

And if it's weight, the Stinger is pretty darn close. If it's power to wheels, RWD is 100% rear; AWD can be 50% but Sport puts 80% back there. What is the possible advantage of that?

Weight distribution I suspect.

The natural inclination of an object travelling at a given velocity is to continue to travel at that given velocity. Note I didn't say speed - velocity includes speed AND direction of travel. Thus, all other things being equal, cars will naturally understeer - they want to continue to move in the same direction and speed as they were before the steering change (and resultant change in direction of forces acting on the vehicle) occurs.

That balance though (wanting to maintain speed and direction) is impacted by lots of things though. There's plenty of resistance to travelling forward (air resistance, rolling resistance from the tyres, etc), but that's largely countered by forward thrust from the engine/drivetrain (which also has to counter drivetrain losses too).

Steering angle requests a change in direction of travel (it imparts a lateral force on the object - the car in this case) - lateral grip will determine whether a car will change direction at a given speed, and by how much.

So where does weight balance impact this?

Let's say you're trying to turn left, and all the weight is in the front of the vehicle. That weight wants to keep moving ahead, and so the weight drags the car outwards in the curve - understeer. The rear follows, because its weight contributes very little to the overall momentum of the vehicle.

This is why front-engined front-wheel drive cars tend to understeer - plough understeer for vehicles that have very heavy engines (large old iron block engines for example) - all the weight of the engine AND gearbox are in the front, and it dictates the behaviour of the car.

If you're turning left and all the weight is in the rear of the vehicle, the car will oversteer. Why? The front of the car, with little momentum, will allow grip to dictate the path it takes. The rear of the car though wants to keep moving straight ahead, and as the nose turns, that momentum goes from being inline with the direction of travel to being at an angle to it - the rear will now want to move straight ahead (to the original direction of travel) faster than the front of the car is moving in the same direction (the front maintains angular velocity, the rear maintains linear velocity).

This is why Porsche 911s (in particular old RWD ones) are notorious for oversteer - they have their engine AND gearbox in the rear, and the rear of the car acts like a pendulum.

A front-engined RWD car with good weight balance will be as neutral as possible, because the front and rear of the vehicle have similar momentum.

Power delivery changes this a little - FWD vs RWD vs AWD because of where power (linear acceleration) is applied, and the impact that has on the balance of grip. Good frontal grip on a FWD car can actually reduce understeer as the car "pulls" itself into a corner - power is being applied in a direction that the driver intends, rather than the direction that momentum dictates. RWD can induce more oversteer because it pushes the rear of the car in the same direction as momentum. AWD mostly helps because it splits the power between four contact patches rather than two - halving the power (actually, torque) output per wheel to the ground, meaning that, when power is being applied (AWD largely doesn't help when you're not applying power - at least for the purposes of this argument) there's less chance of that torque exceeding the grip co-efficient (particularly useful when grip is compromised by cold/wet/etc conditions (wet is obvious, cold often means that tyres haven't come up to their ideal operating temperature, and will grip less than warmer tyres).


Woah. That got bigger than I thought.

 

[Waynerm002]

Thanks for the write up on this! What you went through with the wrenches, sockets, breaker bar, etc,. was exactly what we went through on Monday. We hit up harbor freight to pick up every thing we figured could help and returned what we didn't need. I'll have to drive my buddy's car to really see how it handles to see if I'll want to add one to my car.

 

[MerlintheMad]

Woah. That got bigger than I thought.

Thanks for all of it. You were obviously enjoying yourself too, which is the added bonus a teacher gets. I know I've heard all of this before. But lacking a vehicle to enjoy cornering with, most of it simply bounced off, before.

So 20% front 80% rear (Sport mode) will mitigate understeer; might even bring on some oversteer. I'm fighting oversteer (especially when I had the Nitto Motivo A/S on). I've put the Eibach on soft, which reduces understeer; but Sport mode might be reducing understeer even more, and could, under heavier G in cornering, result in oversteer. Custom mode, retaining Sport for the suspension, but choosing Comfort/Eco for engine/transmission, should retain 50/50 for power output with AWD. I wonder how hard I'd have to push it in a corner to tell any difference between Sport (20/80) and Comfort (50/50) vis-à-vis understeer and oversteer?

 

[Kazz]

Excellent write-up! Thanks!

You noted the slots. Were those only for the firmer setting and soft are round holes?

 

[MerlintheMad]

Excellent write-up! Thanks!

You noted the slots. Were those only for the firmer setting and soft are round holes?

I think he confirmed that the OE bar has slots. The Eibach has two sets of holes on the end. "Soft" is the furthest setting out.

The OE bar looks like this:

The "slots" must be inside the two permanently attached bushings. As you can see, the bushings are not lubricated, they are a flexible (rubberized) internal sleeve gripping the bar, inside the metal bolt on "fasteners".

 

[ZyroXZ2]

Excellent write-up! Thanks!

You noted the slots. Were those only for the firmer setting and soft are round holes?

No no: the Eibach brackets are slotted. This has nothing to do with the bars themselves: the bars just have the two holes at the end.

I think he confirmed that the OE bar has slots. The Eibach has two sets of holes on the end. "Soft" is the furthest setting out.

The OE bar looks like this:
View attachment 25134 View attachment 25135 View attachment 25136
The "slots" must be inside the two permanently attached bushings. As you can see, the bushings are not lubricated, they are a flexible (rubberized) internal sleeve gripping the bar, inside the metal bolt on "fasteners".

The OE bar does not have slots, it's just holes as you can see in your pics on the bracket. The Eibach bracket does not have holes, but slots. The slots allow the bracket, bushing, and thus swaybar to slide up and down the holes on the subframe.

 

[MerlintheMad]

The OE bar does not have slots, it's just holes as you can see in your pics on the bracket. The Eibach bracket does not have holes, but slots. The slots allow the bracket, bushing, and thus swaybar to slide up and down the holes on the subframe.

"Holes", "slots", I am confused. The Eibach has two holes on the ends of the bar. I have no idea what the bar looks like vis-à-vis bushings compared to the OE bar. I've seen the Eibach installed, of course.

Earlier discussion has me wondering what "locked" or "rotating" applies to. What is the difference between the OE bushing and the Eibach bushing? What "slots"? The holes on the ends of either bar look the same to me; the OE only has one set of holes, the Eibach "soft" and "stiff" setting holes.

I guess it would help if I had bothered to take the Eibach out and look at it before installation. Heh!

 

[ZyroXZ2]

"Holes", "slots", I am confused. The Eibach has two holes on the ends of the bar. I have no idea what the bar looks like vis-à-vis bushings compared to the OE bar. I've seen the Eibach installed, of course.
View attachment 25140
Earlier discussion has me wondering what "locked" or "rotating" applies to. What is the difference between the OE bushing and the Eibach bushing? What "slots"? The holes on the ends of either bar look the same to me; the OE only has one set of holes, the Eibach "soft" and "stiff" setting holes.

I guess it would help if I had bothered to take the Eibach out and look at it before installation. Heh!

I hate using bold lettering because it always offends someone, but I've said brackets multiple times, lol... In your pic, that's the triangle looking thingy that holds the bushing against the swaybar and bolts down onto the frame. You're looking at where the endlink bolts to.

 

[Kazz]

OK guys - thanks for the reading lesson. It's the brackets that have the slots. But why the hell would they? The brackets aren't supposed to move within the range of the slots, that'd be stupid and wear out parts. WTF?