[drummr8]

Based on what I see in RealOEM, it appears our cars come with non-sport strut mounts (31306785962). When upgrading the suspension, do you guys use the sport mounts (31306775098) or just replace with new non-sport mounts? I am installing ST Coilovers, and wasn't sure if the sport mounts would be an upgrade or cause issues. Thanks!

[relative4]

Anyone know if the sport mounts are lower? I just installed Dinan springs, and the front is WAY high.

[Soravia]

31306775098

[drummr8]

Originally Posted by relative4

Anyone know if the sport mounts are lower? I just installed Dinan springs, and the front is WAY high.

from what I've read, it seems the sport mounts are slightly lower (thinner?). I'm not sure if there could be some negative impact by using the sport mounts instead of the XI (non-sport) mounts. I don't really see how it could have a negative impact, but was hoping someone else might know for sure.

[vilord]

Originally Posted by drummr8

from what I've read, it seems the sport mounts are slightly lower (thinner?). I'm not sure if there could be some negative impact by using the sport mounts instead of the XI (non-sport) mounts. I don't really see how it could have a negative impact, but was hoping someone else might know for sure.

Did you end up trying the non-xdrive sport mounts?
From what I've gathered in all my searching, they're just stiffer, and maybe slightly thinner.

[Tambohamilton]

Sport mounts are around 5mm lower (actually about 3mm, I think), and Xd around 13mm:

https://translate.googleusercontent...._MnaV3dwMmdYiw

[vilord]

Interesting! So going from xdrive to sport I will be raising my front by a third of an inch.

Guess I'll test this one out, I have a set on order from FCP

[Tambohamilton]

No need to test it unless you want to; I can confirm the measurements from the German site are reasonable approximations of the actual differences in height.

[vilord]

Any idea about stiffness in the different parts?
My intention was to go with the sport mounts because I'd heard they were less noodley.

[Tambohamilton]

So far as I can tell from looking at them, the stiffness should be pretty similar. The sport mounts have a steel body instead of aluminium on the non-sport, I think, but the rubber parts seem to have very similar dimensions and the bearings are the same.
...I think. So I think the stiffness should be similar, unless the rubber is a significantly different compound.

The xD has a much sturdier base; thick cast aluminium with ribs, but the rubber part looks different enough (shallower) that it could completely negate the extra stiffness of the metal part.

In short, there's no way of telling without testing or factory specs, but it would be reasonable to assume that functionally they're not hugely different from each other in terms of stiffness.

[vilord]

probably no good way to effectively test either, except to buy both new, run both for 2000 miles each, then swap back and forth... i'm way too lazy for that.

[Tambohamilton]

You could test them using a spring tester (press with a load cell and deflection measurement)...but of course that wouldn't tell you how any measured differences would translate into road feel. Whichever way, it's far too much work for me too, and I don't have the equipment for the stiffness testing.

[drummr8]

I ended up just getting the normal xDrive mounts, didn't want to mess with it. It seems that the sport mounts would work fine and they're cheaper.

[Tambohamilton]

Good choice. Sport mounts would fit absolutely fine, but with ~8mm higher ride height.