We recently redesigned the billet coaxial mounts for our Xidas. Along with reducing the price a bunch, we added adapters to be able to run these with just about any 10 or 12mm pin Miata shock.
Before asking if they'll fit yours, the answer is yes if they:

• Have 10 or 12mm pins
• Use 2.25", 2.5" or 70mm springs

Default Xida BCM's will fit any shock with a 12mm threaded shaft and 2.25" springs.

Optional 2.5" and 70mm (Tein) spring perches
Optional 10mm shaft adapters. Reuse whatever top nut you have now.

 

Look nice. Pricing is per individual mount?

 

An example of our BCM's (Billet Coaxial Mounts) on a set of Tein Flex.
10mm shaft adapters and 70mm spring perch options..voila!

Same can be done for Bilsteins, Koni's, MCS, Penske you name it. Just measure your shock shaft diameter and know what spring diameters your sleeves are.

Despite the overall size difference, the installed height is exactly the same. The spring sits lower on the coilover but the ride height remains unchanged. No change to bump travel, but all the stiction and binding of the fix perch eliminated.


Demonstrating the range of motion with the coaxial or "floating" spring perch.


In situ




Not Xidas but this car stayed in a Holiday Inn Express parking lot last night. Getting an EDFC on there might require a thinner top nut. The bigger bearing and thicker mount uses up most of the threads.

 

Have you been able to measure the amount of degree change of the coaxial mount under compression?

 

Never tried. Don't need to know how hot the skillet is, just that it's hot enough to require an oven mitt. Springs deflect, twist and bending when compressed, we don't need to know precisely how much.

The plane of the body changes relative angle to the lower mount as the control arm swings through it's travel. This is a separate but just as important deflection acting on the springs that a fixed mount does not address, coaxial mounts do.

Two birds, one stone. Letting the damper do it's job with fewer extraneous loads and binding forces imposed.

 

Xida Upper Mount Miata BLEM

Is that price for 1 or for 4?

 

It's per two.

 

I'm an idiot. "This pair"