MPP Comfort Non-adjustable+Eibach Sway Bar resulted in Jumpy/Bouncy drive

[northcalhill]

Hi All, i had Mountain Pass Performance Comfort Non-Adjustable installed in my M3LR 2020 few months ago, the ride was absolutely comfortable, road noise was almost non-existed with the new coilover . I am living in a mountainous area where cracked road are everywhere, when getting over the road hump or a road with cracked surface , the ride is a bit floaty but you can definitely feel that the shock is absorbed and spread away.

To me it was absolutely amazing until I replaced the OEM front & rear sway bar with Eibach sway bar few weeks ago, the ride quality was started to become disastrous. When the car passing through an uneven surface (especially low speed in carpark ), it jumps left and right continuously , i had a feeling that my car keeps vibrating involuntary (i know that it is how a robust sway bar works , it tries to balance a pairs of wheel from one side in positioning with another side). Since current MPP coilover is non-adjustable yet the spring is pretty soft, I have no way to adjust the rebound and compression rate to tackle the problem, only I can do is to unplug a pair of Eibach sway bars.

MountainPass/ Guys, do you have any idea to resolve this problem?

Anyway, I had just ordered a new MPP Comfort Adjustable with local dealer few days ago and going to sell my non-adjustable version very soon. In the hope that by adjusting the rebound/compression rate in adjustable version with the installed Eibach sway bar , the bouncy feeling can be gone .

I ride with my family daily on the mountainous road everyday. Is it better to go for MPP Sport version (with softest setting) or go for MPP Comfort Adjustable (with harsh setting) ? I can still change my mind at the moment. Appreciate if you can offer your insight. Thanks

 

[MasterC17]

I'll let others chime in, but my experience is that the stock front sway bar especially is plenty big enough for this chassis, and going bigger can negatively impact handling and ride comfort. I nearly threw out my UP front sway bar in the trash. What a pile of garbage. Eibach is better quality, but suffers from similar issues.

I would also avoid adjustable endlinks. You are adding NVH and aggravation for no measurable gain.

My opinion - put the stock sway bars and end links back on the car. I do not think the adjustable suspension is going to solve your problem.

 

[SteelClouds]

So this goes back to the two schools of thought regarding handling. Years ago there were "loud" debates over soft suspension with travel vs stiff and little travel as to which was better on a given car. Stiff springs, small sway bars and poly bushings were all the rage. Guys even tried to use tube anti roll bars like on real track cars but thats just way too stiff for street use. Made for an awesome track car and one that just sucked for a daily driver. The other side was softer progressive springs with a big a** anti-roll ( sway ) bar with modified poly bushings and such. Yes, the car would lean a bit more but it was very controlled as the "soft" ( very relative) would soak up the bumps and hits vs skipping over them. Definitely more street friendly.

Personally speaking based on my OWN experience, I would pull the Eibach bar off, put the OEM back on and call it a day. Progressive springs and decent struts for rebound control are king on the street. I would be very hesitant with coil overs only because getting replacement parts later on can be problematic. You want the suspension to be able to take the initial hit and absorb it while still tracking up over and down whatever it was. Too stiff and you hit then bounce over because the suspension cannot track it. I made that mistake on a car and almost changed lanes one night when the back unexpectedly bounced on a hole in the road and threw the back sideways.

 

[Mash]

Anti sway bars are bandaid with their own disadvantage. It decreases suspension independence. So if you have a bump on the left, it will offload the right side too. If you have a long dip on one side it will slow down wheel planting. So it's not only feels worse, but it also messes up with traction predictability.

Model 3 front becomes significantly worse with anything stiffer than stock bar. Rear can be slightly improved with more stiffness. But if roads are full of long pots, I would keep stock bars on both sides.

 

[Theadonnan]

Try reverting to stock front bar, but keep aftermarket rear and report back?

 

[coolioj]

FWIW - I've been on MPP Comfort non-adjustable coilers since the beginning of 2020. I just installed my Eibach sway bars this past Saturday. While I did notice a bit less of independence between the left and right, I didn't think it was significant. I even asked my wife, if she thought the car was more "rough" on a 30 mile drive to my parents house, which she would be the first to notice, but she said it felt the same. I used the center hole on the front bar, and the "stiffer" hole on the back. This resulted in less understeer, and more neutral go kart feel. I am happy with how the car handles now. Ride is definitely subjective though.

 

[enigmata]

What are your sway bar settings? Stock end links?
I know I can't tolerate more than front soft on my UP sway bar on my RWD. Getting the front sway bar on nearly made me regret the choice on my RWD because of all the weight it added. For the first time I had to switch to steering mode comfort just to get used to the steering feel again.

 

[jackmott]

Your problems began with a sway bar install and you are trying to resolve it with a new coilover?
Just remove the sway bars, big swaybars have ride quality downsides, many people on the internet wrongly state that they don't. Car is likely faster with factory ones too.

 

[Ren.OG]

Did you adjust for preload during install?
Are you using soft setting on the bars?

 

[MountainPass]

I couldn't have said it better than these fine folks! Thank you all for being such a great resource.

 

[dfwatt]

Hi All, i had Mountain Pass Performance Comfort Non-Adjustable installed in my M3LR 2020 few months ago, the ride was absolutely comfortable, road noise was almost non-existed with the new coilover . I am living in a mountainous area where cracked road are everywhere, when getting over the road hump or a road with cracked surface , the ride is a bit floaty but you can definitely feel that the shock is absorbed and spread away.

To me it was absolutely amazing until I replaced the OEM front & rear sway bar with Eibach sway bar few weeks ago, the ride quality was started to become disastrous. When the car passing through an uneven surface (especially low speed in carpark ), it jumps left and right continuously , i had a feeling that my car keeps vibrating involuntary (i know that it is how a robust sway bar works , it tries to balance a pairs of wheel from one side in positioning with another side). Since current MPP coilover is non-adjustable yet the spring is pretty soft, I have no way to adjust the rebound and compression rate to tackle the problem, only I can do is to unplug a pair of Eibach sway bars.

MountainPass/ Guys, do you have any idea to resolve this problem?

Anyway, I had just ordered a new MPP Comfort Adjustable with local dealer few days ago and going to sell my non-adjustable version very soon. In the hope that by adjusting the rebound/compression rate in adjustable version with the installed Eibach sway bar , the bouncy feeling can be gone .

I ride with my family daily on the mountainous road everyday. Is it better to go for MPP Sport version (with softest setting) or go for MPP Comfort Adjustable (with harsh setting) ? I can still change my mind at the moment. Appreciate if you can offer your insight. Thanks

As everyone has already indicated, dump the aftermarket sway bar. Front roll stiffness with a stock bar is enough unless you're a track Junkie.

 

[Mash]

As everyone has already indicated, dump the aftermarket sway bar. Front roll stiffness with a stock bar is enough unless you're a track Junkie.

Pikes Peak model 3 uses stock front bar...

 

[northcalhill]

Hi All, thanks for all constructive recommendations.

Originally , I had medium setting (2nd /3 holes) in the front Eibach sway bar and firmest in rear (2nd/ 2 holes) .Even though I switched both front and rear Eibach sway bar in "softest" setting (1st /3 holes) in the front and (1st/2 holes) respectively, the jumpy feeling still persists . Gonna revert my front OEM sway bar first , see how it goes and determine whether I need to replace the rear one as well.

I am anticipating for the delivery of new MPP Comfort Adjustable Coilovers, local dealer said it takes 6 weeks to ship over from Germany

 

[Motion122]

Hi All, i had Mountain Pass Performance Comfort Non-Adjustable installed in my M3LR 2020 few months ago, the ride was absolutely comfortable, road noise was almost non-existed with the new coilover . I am living in a mountainous area where cracked road are everywhere, when getting over the road hump or a road with cracked surface , the ride is a bit floaty but you can definitely feel that the shock is absorbed and spread away.

To me it was absolutely amazing until I replaced the OEM front & rear sway bar with Eibach sway bar few weeks ago, the ride quality was started to become disastrous. When the car passing through an uneven surface (especially low speed in carpark ), it jumps left and right continuously , i had a feeling that my car keeps vibrating involuntary (i know that it is how a robust sway bar works , it tries to balance a pairs of wheel from one side in positioning with another side). Since current MPP coilover is non-adjustable yet the spring is pretty soft, I have no way to adjust the rebound and compression rate to tackle the problem, only I can do is to unplug a pair of Eibach sway bars.

MountainPass/ Guys, do you have any idea to resolve this problem?

Anyway, I had just ordered a new MPP Comfort Adjustable with local dealer few days ago and going to sell my non-adjustable version very soon. In the hope that by adjusting the rebound/compression rate in adjustable version with the installed Eibach sway bar , the bouncy feeling can be gone .

I ride with my family daily on the mountainous road everyday. Is it better to go for MPP Sport version (with softest setting) or go for MPP Comfort Adjustable (with harsh setting) ? I can still change my mind at the moment. Appreciate if you can offer your insight. Thanks

Keep in mind that adding anti roll bars also adds spring rates to the suspension and you will need more damping. With proper coilovers you should be fine with OEM bars. I am taking mine off after the MCS 2WNR install. I have plenty of springs for dive, squad and roll control.

 

[Mash]

Keep in mind that adding anti roll bars also adds spring rates to the suspension and you will need more damping. With proper coilovers you should be fine with OEM bars. I am taking mine off after the MCS 2WNR install. I have plenty of springs for dive, squad and roll control.

You're taking anti sway bars off completely? I would be testing that idea really carefully.

 

[Motion122]

You're taking anti sway bars off completely? I would be testing that idea really carefully.

I am responding to the OP with aftermarket bars. I am taking my aftermarkets ones off. From experience the vehicle should be fine without a rear bar but will likely need the front.

 

[Mash]

Stock rear is needed even on a twice stiffer rear springs. I was scraping battery edges on a long turns with Cup2 tires even with harder rear sway bar than stock. I can't imagine that removing rear bar can work - I think springs would have to be extremely stiff and degrade even track traction.

 

[Motion122]

Stock rear is needed even on a twice stiffer rear springs. I was scraping battery edges on a long turns with Cup2 tires even with harder rear sway bar than stock. I can't imagine that removing rear bar can work - I think springs would have to be extremely stiff and degrade even track traction.

You got some sticky tires there. Perfect they will work even better and keep your battery off of the track surface with higher spring rates. Have you done any testing to see if you are sitting on your secondary springs when your battery starts to scrape? More mechanical grip is always welcome, but It's all about your particular setup, track and fine tuning.

 

[thesmokingman]

^^Yea, I was wondering what kinda compounds is he must be running get that sort of compression?

 

[Mash]

^^Yea, I was wondering what kinda compounds is he must be running get that sort of compression?

It's not about tires as much as about track. Carousel on the Ring is particularly tough spot. I'm just saying that I don't think it's a good idea to remove rear sway bar for track use - either springs won't keep it or they will be so hard that there will be a bad weight transfer with traction loss.