Bouncy ride on Eibach Prolines Springs - 2019 Mustang GT

[speedo]

Greetings everyone.

I have some Eibach Proline springs installed on my 2019 Mustang GT PP1. Since then I've noticed a bouncy ride since I've installed them about 6 months ago. Everything was tightened to the required specs according to the Mustang GT suspension sheet. My car has 20k miles on it and has been driven about 4k miles with the Eibach Springs. I knew the bumpy ride was expected after I installed them but I wanted my car to handle better which it does and I do not plan on putting the old stock springs back on.

Does anyone know what I need to do to remove the bouncy ride without installing new springs? A performance shop near by told me that there is nothing I can do and that my stock shocks and struts should handle the Prolines.

Thanks.

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[Brian@BMVK]

Pro-kit or Sportline? You seem to have combined them both.

Your stock dampers are barely adequate for the Pro-kit, and not at all with the Sportlines. Did you use the Eibach bumpstops or oem?

 

[speedo]

Pro-kit or Sportline? You seem to have combined them both.

Your stock dampers are barely adequate for the Pro-kit, and not at all with the Sportlines. Did you use the Eibach bumpstops or oem?

Thanks for the reply. They are the Sportlines with the Eibach bumpstops.

Thanks.

 

[garagelogic]

Greetings everyone.

I have some Eibach Proline springs installed on my 2019 Mustang GT PP1. Since then I've noticed a bouncy ride since I've installed them about 6 months ago. Everything was tightened to the required specs according to the Mustang GT suspension sheet. My car has 20k miles on it and has been driven about 4k miles with the Eibach Springs. I knew the bumpy ride was expected after I installed them but I wanted my car to handle better which it does and I do not plan on putting the old stock springs back on.

Does anyone know what I need to do to remove the bouncy ride without installing new springs? A performance shop near by told me that there is nothing I can do and that my stock shocks and struts should handle the Prolines.

Thanks.

The problem is not the springs, it the fact that you are using the stock struts/shock with the new equipment. The stock units are valved for the stock springs. Obviously, they will function with aftermarket springs, but they will exhibit the kind of 'bounce" that you are experiencing.

 

[StangTime]

There's an easy fix for getting rid of the bounce. Replace the dampers with the Ford Performance Track versions. That's all I did on my PP1 and it feels like a whole different car. BUT... if I were to do it again, I would buy the dampers and the struts as a package because it's cheaper if you will eventually change the struts too. I bought the dampers used on the forum. But now I would like to lower the car and get the matching struts for the front.

This is what is highly recommended: https://www.levittownfordparts.com/sku/m-18000-f.html
And just getting 2 of these will solve your bounce: https://www.levittownfordparts.com/sku/m-18001-as.html

 

[Vicr]

You can't run OEM dampers with Sportlines. I have the Koni yellow's which are adjustable for different road/track environments. Sportlines also will cause bumpsteer and you may want to get the Steeda Bumpsteer kit to correct the geometry issue the Sportlines create. While changing dampers you also will want to install Camber plates to have the alignment done with full adjustability.

 

[Dave2013M3]

Thanks for the reply. They are the Sportlines with the Eibach bumpstops.

Thanks.

Brian just answered your question. Your car is underdamped. Time to move on to FR shocks or equivalent. The OEM dampers when you go beyond a 1" drop are way out of their valving. Not to mention they weren't even adequate for the OEM PP1 car.

 

[007evan]

get some koni's. That will take car of the problem. I tossed my pp1 setup.

 

[speedo]

Thank you guys for the replies. I will probably go with the full package that Brian mentioned. I plan on doing this in my garage myself.

I will provide an update when I get them installed.

Thanks.

 

[speedo]

Hope everyone is doing well. So I went ahead and ordered the Koni Strut and Shock kit for my 2019 Mustand GT from CJ Pony Parts last week. Yesterday I received a package outside my door step but notice something loose when i picked it up. I knew this was not good. After i decided to do a full inspection and take pictures just in case and this is what happened. I saw a few tears around the box but didn't think it was a big deal.. But then when i opened the Bigger box I noticed that the packaging was very poor. There was only one piece of bubble wrap that didn't really protect anything. One of the strut's shaft punched a hole through it's individual box and was sticking out of the box . It also seems like the wire that holds the shaft down from releasing came loose on both struts. The rear dampers also were not package properly. One box was opened and looks like someone just shoved the shock in the box with instructions. Everything was loose in thier boxes. Not good folks.

Overall i was really disappointed with how they did the packaging from the warehouse. I did call CJ Pony parts and told them and they said they will send me a pre-paid label to return all items and ship me new ones. Although i did not see any exterior damages and all the parts look new im curious if the parts are good so they can be installed.

Anyway looks like i might need to wait longer on this now unless i decide install them.

Has anyone else experienced any poor packaged struts or shocks from CJ or other shops and still installed them?

Just curious.

 

[Vicr]

When I recieved my Koni yellows from AM one of the boxes was in rough shape but the strut looked OK. After paying for installation and alignment the mechanic at the shop took it for a test drive and there was clunking from the right front strut area. Sure enough it was a bad strut. Yup, send em back.

 

[StangTime]

It seems to be a rare case nowadays to expect these big online parts sellers to actually pack something with enough care to survive shipping. Thanks for the review @speedo .

 

[fast306stang]

Since then I've noticed a bouncy ride since I've installed them about 6 months ago.

What are you considering a bumpy ride?

I put SportLines on my 2018 PP1 with 8K miles on it and it handled better than when it was factory with just a little bit more harshness in ride but nothing unexpected or terrible. I'm wondering if something else might be the issue. There's a thread here about pre-load on the bushings, I wonder if that's not the case?

 

[Chomorro]

I bought my car used and lowered on blue springs unsure if the manufacturer of the springs but it looks nice. The ride is very smooth except you feel little bumps that slightly jolt you a little. On flat freeway and curves it handles fantastic but those little bumps remind me if when I was 18 in my honda lol.

I jacked it up but I cant tell if the shocks are oem pp1. It looks like they might be. Following to see how yours handles after the upgrade!

 

[speedo]

Hi Guys. So I decided to keep them and take my chances since I did not see any exterior damages. I did Call CJ Parts and i did ask for a refund for the bad packaging and they gave me a refund for the shipping (about 70.00). Not much but i did want to go through the time and money to send these back only to get the same stuff back. Any way installation went good but with some after installation issues and I need some advice on what to do next and have some questions from you guys....

So, It took me almost 2 days because i took alot of breaks and did it myself and I also had to run to stores to get parts like the spring compressor , a 15/32 drill bit and a spring compressor. Front was the longest and the rears were the easiest. I did notice that my rear stock shocks were shot on both sides. Probably because riding them so long on my Eibach Sportlines. Anyway, after the installation i took it for a drive and notice a small difference. Still bumpy ride so I took it back and adjusted them to a softer setting. About 1 and half turns front and rear adjustments and i did feel a difference. Not a huge improvement but better than what I had with the stock struts and dampers. Overall I am happy with them. Installation was a pain but it was fun and a good learning experience.

Now for the the issues..

1. I have negative camber now on my front tires which i didn't have before with my stock struts.. I'm not sure if this is normal after the strut installation. I heard that the Camber plates will fix this but I dont want to go through installing them. Removing that strut and spring is a pain in the ass and takes to much time.

Is it safe to drive the car with negative camber? What do you guys recommend that will fix this?

2. Do I need an alignment? Im sure this is a Yes answer but just wanted to make sure.

Thanks!

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