OVERVIEW
The ST XTA coilover kit for the E85 Z4 roadster brings independent height and rebound damping adjustment plus camber-adjustable top mounts to a chassis that responds well to a lower center of gravity.
ST is the value brand of KW Automotive. The XTA sits at the top of the ST coilover range: height adjustable, with 16 distinct clicks of rebound damping adjustment and aluminum unibal top mounts that also allow camber adjustment. The struts are galvanized zinc-coated steel and the spring perch is a composite polyamide item with a stainless steel insert. The kit ships factory-preset and includes a damper setup manual.
SPECS
- Damper family: ST XTA (height and rebound adjustable, adjustable top mounts)
- Front lowering range: 0.8 in to 2.0 in
- Rear lowering range: 0.6 in to 1.6 in
- Damping adjustment: rebound, 16 distinct clicks
- Top mounts: aluminum unibal, camber adjustable
- Strut material and finish: galvanized zinc-coated steel
- Spring perch: composite polyamide with stainless steel insert
PARTS INCLUDED
- Complete coilover kit as supplied by ST Suspensions; see the installation instructions included in the box for the full bill of materials.
TECH RESOURCES
Additional Parts Required
- Four-wheel alignment. A full four-wheel alignment is mandatory after installation and after any subsequent ride-height change.
- Professional installation. Spring compressors and strut service tools are required.
- Check EDC compatibility. This is a passive coilover kit that replaces the OEM dampers. Confirm your car is not fitted with Electronic Damping Control before ordering.
Installation
- Vehicle-specific installation instructions are supplied in the box with the kit.
- A damper setup manual with ST's reference rebound settings is supplied with the kit.
- ST does not publish a public download link for this kit's instruction sheet. Contact Speed Logic if you need a copy before the kit arrives.
Notes
- E85 roadster only; the E86 coupe uses a different part number.
PART NUMBER
- 18220804
VEHICLE APPLICATIONS
| Make / Model | Chassis | Engine | Years |
|---|---|---|---|
| BMW Z4 2.5i | E85 | M54 2.5L I6 | 2003–2008 |
| BMW Z4 3.0i | E85 | M54 3.0L I6 | 2003–2008 |
| BMW Z4 3.0si | E85 | N52 3.0L I6 | 2003–2008 |