Bump Steer Plates Make All The Difference In Feel For Lowered Cars

Posted by:

Often times, the our pursuit for better suspension performance (i.e. lowering, tire changes, etc.) we overlook how our adaptations can negatively affect the performance the BMW engineers already built into our cars. Namely we make our changes using the best possible information and experience out there only to find that the smooth, driving performance characteristics that we’ve come to know and love about BMW, have vanished from our car.

After lowering the CSi with Eibach springs and installing Bilstein HD valved shocks and strut inserts, the ride improved from a controllability perspective but some of its ‘surefootedness’ vanished; and it bugged me to no end – especially on unstable ground that we all encounter every day.

Lowering your car will have a negative impact on the geometry already built into the E31 suspension. And luckily, thanks to the support from our more senior members of the E31 community, there is a solution that brings back that BMW ride quality. These bump steer plates are one of those solutions.

So I installed these nifty custom made plates in the CSi today and MAN what a different it makes with the Eibach springs! Went over many bumps and a little washboard in the road and the car felt more like itself, more sure of itself in general and especially at turn in.

I’m not understanding all the geometry but it sure made the car feel more solid! Other enthusiasts believe that the greatest felt effect comes from toe change/bump steer, and that’s the best benefit the plates have to offer.

Credit to 8Tech at Bimmerforums for his write up that makes adding these spacers easy: http://forums.bimmerforums.com/forum/showpost.php?p=21656294&postcount=11

 

2

About the Author:

I am an 8 Series nut. In 2009 I restored a '92 850i to peak condition and subsequently sold it - which left me depressed. So I embarked on catching my White Whale: this '95 850CSi Chassis #CD00166. I’m opinionated and swear constantly, but I have friends in spite of myself. I am funnier than my wife realizes. Please tell her. Cheers!

Comments

  1. 97 8ster  May 23, 2014

    Hello,
    I have a 97 840CI that’s a DAILY DRIVER in pristine shape. I have had the car for almost 8 years now. My shocks need replacing and I think I would like to lower the suspension a little. I bought Eibach lowering shocks which claim to lower 1″ front and .75″ rear. I want to get Bilstein shocks. All they offer is sports. I wish to maintain the “luxury” in the ride. I am reading blogs and see that the bump steer plates may be an essential piece of the solution. I see that there was a lot of back and forth 3-4 years ago regarding them. Now that they have been field tested, is there any down side to having them? Also, do the Bilsteins need any revalving of the sport shocks? I would really appreciate any help you could afford me in this regard as I am on a tight budget these days and need to get it right on the first attempt.
    Thank you,
    Billy

    reply
    • admin  May 23, 2014

      Hi Billy,

      Yes bump steer plates for lowered E31s have been very well field tested by a lot of people. I cannot speak for anyone else but in my case they made a noticable difference in how sure footed the car feels over imperfect road conditions. I would do them again on any lowered car.

      As to the shocks, in my case I tested Sports, HDs and Comfort valved settings. You can pay Bilstein to valve your shocks to whatever settings you like, by the numbers. But if you don’t know the numbers, best to select one of the above. Sport and Comfort can be bought off the shelf. HDs, which is somewhere in the middle, have to be re-valved by Bilstein. I found the HD setting in combination with the Eibach springs and shocks valved to HD to be the most comfortable ride combined with the most responsive setup – it’s somewhere in the middle of driving the stock land yacht and a tightened up M5 track car.

      reply

Add a Comment