Rear lower control arm endlink/shocks ratio adjustments
 

Hi all,

Just wondering if anyone uses the extra holes (left, center, right) in their adjustable rear lower control arms to tune stiffness for the rear suspension/sway bars.

https://i.imgur.com/h8MJAf0.jpg

Tried looking for information on how much stiffer or softer can we expect when switching to different configurations, not much info on these. Hopefully, some can share their experiences on these.

Aren't those different mount-holes more meant for rather different lowering/drop, then for suspension stiffness tuning? As in if one wishes for extreme drop to relocate lower mountpoint aswell, to keep some of coilovers travel, in similar fashion like special upper mounts do? Leave stiffness tuning to rollbars & coilovers themselves, no?

^^ Those specific holes pointed to by the arrow are to adjust the motion ratio for the sway bar, which would effectively tune the stiffness a bit. The holes are beside each other, not above or below.

Now, the shock mounting point has two rows of three, one above the other, that could be used to gain bump travel.

As for how much stiffer or softer, it's just math based on how much further in/out the extra holes are. It's not going to be a drastic difference though.

Do you happen to have any references on calculating the stiffness in regards to the extra holes?

I would be trying it out to get a butt feel but some numbers would be nice.

You'll have to measure the change in the motion ratio (which would increases as you move the mounting point out towards the wheel).

Wheel rate = spring rate * motion ratio^2

Same for the sway bar. There are estimates of the spring rate of the swaybars floating around somewhere on here.

- Andrew

The extra swaybar holes can be useful if you don't have an adjustable bar and want to make the rear softer or stiffer. Farther out should make it a touch stiffer.

Having a lower hole on the shock mount is also handy if the car is low because it'll give you back some much needed bump travel.

But all those other extra ones for the strut i would probably not ever want to use.