OVERVIEW
H&R Sport Springs are the best-selling performance street springs for BMW, and replacing the factory springs is one of the first and most effective steps in suspension tuning. On the G29 Z4 they close up the fender gap and lower the centre of gravity, which reduces body roll and improves handling and chassis balance while keeping the car driveway-friendly.
The progressive spring rates are increased 10–20% over stock. They remain compliant during normal driving and stiffen as they compress, so the chassis stays composed when the road gets twisty. This kit is specified for cars equipped with the adaptive suspension option.
H&R springs are crafted from a special 54SiCr6 spring steel and shot-peened to increase their life by more than 200%, so they will not settle or sag. All production is completed by H&R in-house, and every spring is 100% tested before leaving the ISO9001-certified production facility in Germany.
SPECS
- Approximate front lowering: 1.0" (sDrive M40i) / 1.3" (sDrive30i)
- Approximate rear lowering: 0.8" (sDrive M40i) / 1.0" (sDrive30i)
- Progressive spring rate, increased 10–20% over stock
- Specified for cars with the adaptive suspension option
- Crafted from special 54SiCr6 spring steel
- Shot-peened to increase spring life by more than 200%
- Will not settle or sag
- All production completed in-house in Germany; each spring 100% tested
- Built to TÜV and ISO9001 quality assurance standards
PARTS INCLUDED
- Complete H&R Sport Spring kit as supplied by H&R Springs — front and rear springs. See the installation instructions for the full bill of materials.
TECH RESOURCES
Required Extras
- None. H&R specifies no additional hardware for this spring kit.
- Four-wheel alignment after installation — H&R states that alignment must be checked after any suspension ride height modification.
- Professional installation — H&R states that its springs and suspensions should be installed by professional suspension mechanics only.
- A spring compressor and standard strut service tools, supplied by the installer, are required to disassemble the factory struts on this spring-only kit.
- Verify your car's damper specification before ordering. This listing is for the adaptive suspension application; cars on standard suspension take a different H&R kit.
Installation
- H&R Technical Information & Installation Guide (PDF) — spring markings (F/VA front, R/HA rear), ride height measurement, bumpstop trimming table, alignment requirements.
- H&R installation FAQ (hrsprings.com) — spring orientation, progressive rate springs, ride height measurement and post-installation alignment.
- Follow the factory service manual procedure for spring replacement on the G29 chassis.
VEHICLE APPLICATIONS
| Make / Model | Chassis | Engine | Years |
|---|---|---|---|
| BMW Z4 sDrive30i | G29 | B48 2.0L Turbo I4 | 2019+ |
| BMW Z4 sDrive M40i | G29 | B58 3.0L Turbo I6 | 2019+ |
H&R's official kit number for this application could not be verified on hrsprings.com, so no part number is published here. Please confirm exact fitment and part number with Speed Logic before ordering.