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Discussion Starter · #1 ·
I'm rolling on fk konigsport coilovers on my 528i...

I used to have it so that the front is lower than the rear...

This is the typical setup with stock and sport suspension as well as some other lowering kits.

It seems that this is so because if you look at the design of e39 chassis from the side, the front seats are located right in the center between front wheels and rear wheels. The rear passenger seats is located almost on top of rear wheels.

As you can imagine, when the car is fully loaded with 5 passengers and luggage in the trunk, the rear goes down a bit. What I've observed is that only the rear goes down, and the front ride height only seems to change a little. So, it makes sense that you would put the rears higher...

Unfortunately, when I had my suspension adjusted about a week ago, my rears ended up being about .5 inch lower than the front with nobody in the car.

But the feel of driving changed a little bit. I could definitely tell during a hard corner that the center of gravity has shifted to the rear, and as a result it made the car corner better, or least it felt like it. It felt very neutral turning into a 90' corner... almost felt like railing through it at about 35~40mph... with just me inside...
Not only that, I can't quite describe it, but the car felt more fun as it felt more like a toy car as the rears felt more heavier. As if the engine was in the rear or something. Of course, only noticeable during hard corners...

Anyhow, I liked how it drives, but I don't like how it looks and how i won't have any rear ground clearance when i have passengers in my car. So, I'm thinking of raising the rears .5 inches to make the car completely level from the side with no one in the car with a full tank of gas.

Many questions came up to my mind as I had this change of driving characteristics....

Of course, the car wasn't aligned since the new change in ride height, so my cambers and toes were more tuned towards turning.. as in more angled cambers and bit of toe out in front.

Anyhow, I also played with the front suspension shock's rebound adjustment, and found my sweet spot again for the new ride height.

Now, here are some questions I came up with for suspension experts out there... Now, I tried searching for these already, but couldn't find definite answers, or anything clear cut.

Given, in a FR cars such as BMW's with 50/50 weight distribution, and the suspension is set perfectly level....

What happens....
1. if the car's front ride height is lowered/heightened a little bit? understeer? oversteer?
2. if the car's rear ride height is lowered/heightened a little bit? understeer? oversteer?
3. if the car's front dampers is set firmer/looser? understeer? oversteer?
4. if the car's rear dampers is set firmer/looser? understeer? oversteer?

also... side questions...
Say the car was perfectly aligned...
What happens...
1. to camber and toe, when you raise/lower the front ride height
2. to camber and toe, when you raise/lower the rear ride height

I'm really curious because I've done BMW alignments from the dealer, and how they set up for my coilovers was the front was perfectly straight with no camber or toe...

and the rear is set up just like an FR should be with little camber and toe in.

I've since raised the front a little bit, and lowered the rear a little bit, and I've gotten some amazing handling out of the car, and I wonder why, because before it used to understeer, or at least tires used to make more noise during hard corners... but now it seems that there is less weight it the front, and the car is able to steer better...

Anybody have good experience with suspension dynamics? and can tell me exactly what's going on in these situations? Thanks.

59 Posts
Better handling is most likely due to toe changes when the ride height was adjusted. I believe the rear toe's out when raised, causing the are to understeer less. Toe changes affects the handling far more dramaticly than any weight shift casued by ride height adjusments. That is assuming that the alignment was reset to the same settings prior to ride height change.
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