What is the practical difference between the piggyback and hose-mounted reservoir options on the A9x GR Supra NTR-R3?

The piggyback reservoir mounts directly to the shock body, keeping the unit compact and self-contained. The hose-mounted reservoir connects via a separate hose, allowing it to be positioned away from the shock body where space or heat management requires it. On the GR Supra, both options are available at the front; the rear runs hose-mounted only. The choice generally comes down to packaging requirements and how the car is being built.

How does 3-way independent adjustment differ from the combined adjustment on the NTR-R1?

The NTR-R1 uses a single adjuster controlling compression and rebound together. The Nitron NTR-R3 coilover separates high speed compression, low speed compression, and rebound into three independent circuits, each with its own adjustment range. That separation gives engineers the ability to tune each damping characteristic on its own terms rather than making compromises across the range with a single control.

Can the NTR-R3 be serviced and revalved?

Yes. Every Nitron NTR-R3 coilover kit is fully serviceable and built to be rebuilt. Seals, oil, shim stacks, and spring rates can all be refreshed or changed independently, and the modular construction means individual dampers can be sent back without pulling the whole kit. For a car in regular track use, that serviceability is what makes the R3 a long-term investment rather than a consumable.

Is the NTR-R3 a significant step up from the NTR-R1 in terms of installation complexity?

The hardware is more involved given the external reservoirs and independent adjustment circuits, but the installation process follows the same principles as any coilover fitment. The hose-mounted reservoirs on the rear require positioning during install, and the three adjustment knobs need to be set before the car goes back on the road, but neither adds meaningful complexity for anyone with coilover installation experience. The bigger difference is in setup depth once the car is on the ground.

Nitron NTR-R3 Coilover Kit for G29 BMW Z4 / A9x Toyota GR Supra

The Nitron NTR-R3 coilover kit for the G29 BMW Z4 and A9x Toyota GR Supra is built for drivers and engineers who want to take full advantage of what both platforms are genuinely capable of. Independent 3-way damping adjustment with separate high and low speed compression control gives the range needed to properly dial either car in across different circuits and conditions. On the Z4, the front units run piggyback reservoirs and the rears use hose-mounted reservoirs; on the GR Supra, the front units are available in either piggyback or hose-mounted configuration with hose-mounted reservoirs at the rear. Coilover and divorced rear suspension configurations are both available for the Z4; the GR Supra runs divorced rear only. A large diameter piston and ultra-strong piston rod sit at the core of the design, providing the damping control and feedback that serious setups depend on, with high and low speed compression adjustment accessible at both ends without adding complexity to the installation. The NTR-R3 coilover is a proven race winner with lap records across a wide range of international motorsport formulas, and every kit is custom built, custom sprung, and fully serviceable. Hard-anodized titanium finish parts and high-grade materials keep corrosion out and weight in check, so the dampers hold their performance standard season after season.

Coilover vs Divorced Rear Suspension

The G29 Z4 NTR-R3 is available with two rear suspension configurations depending on how the car is being built. The coilover setup combines the spring and damper into a single unit, keeping things compact and straightforward for road and general track use. The divorced configuration separates the spring and damper, allowing each to be positioned and tuned independently; this is the preferred approach for dedicated race builds where maximizing suspension geometry and setup flexibility matters more than packaging simplicity. Nitron offers both to make sure the NTR-R3 works with the build rather than against it.
The A90 and A91 GR Supra NTR-R3 is available in the divorced rear suspension configuration only. The divorced setup separates the spring and damper, allowing each to be positioned and tuned independently rather than packaging both into a single coilover unit. This suits the GR Supra’s rear suspension geometry and gives dedicated builds the setup flexibility to extract the most from the platform without compromising damper positioning or spring rate tuning.

Specialized Bi-Axis Hose Fittings

Nitron R3 Hose shocks use Nitron’s own 720 degree Bi-Axis fittings exclusively; a proprietary design that delivers clean, precise installation without the fitment compromises that come with conventional end fittings.

Unique Technology

Nitron builds every shock from precision components that go through a thorough design and development process well before final assembly. The modular construction gives engineers the flexibility to approach each application on its own terms without cutting corners on part quality or how components perform together under load. Everything is machined to tight tolerances and inspected individually by trained technicians, with quality control running through every stage of production rather than being concentrated at the end. New materials, finishes, and processes are validated extensively before adoption, with proprietary Nitron technologies integrated throughout to produce shocks that consistently hold up against the competition on road and track. That engineering standard is what the brand has been built on since 1998.
- Basic Damper Design:
  1. End Eye / Top Mount
  2. Damper Piston & Shim Stack
  3. Shaft / Rod
  4. Floating / Separator Piston
  5. Suspension Oil
  6. Compressed Nitrogen Gas

Bespoke Engineering

Nitron doesn’t adapt a generic damper to fit the GR Supra / Z4; they engineer one around it. Every application goes through a dedicated development process where components, spring rates, and damping characteristics are determined by the specific platform, not borrowed from something close enough. The geometry, weight distribution, and suspension travel of the chassis are part of the design from the beginning, not corrections introduced later. That’s the difference between suspension that works with a car and suspension that was developed for it.

Features

Coilover or divorced rear suspension types
Piggyback & hose reservoir types
16 clicks of high compression
26 clicks of low compression
24 clicks of rebound
Preload adjuster
3-way independent adjustment
Full alloy body
Consists of 4 coilovers, reservoirs, hoses, and top mounts
Hand made to order

Specifications

Coilover Type: NTR-R3
Adjustment Type: 3-way independent
Adjustment: 16 clicks of high compression / 26 clicks of low compression / 24 clicks of rebound
Reservoir Type:
- G29 Z4:
  - Front: Piggyback
  - Rear: Hose
- A90 / A91 GR Supra:
  - Front:
    - Hose
    - Piggyback
  - Rear: Hose
Rear Suspension Types:
- G29 Z4:
  - Coilover
  - Divorced
- A90 / A91 GR Supra:
  - Divorced
Droplinks Included: No
Recommended Spring Rates:
- G29 Z4:
  - FRS – Fast Road Spec:
    - Front: 343lbs/inch (60N/mm)
    - Rear:
      - Coilover: 300lbs/inch (53N/mm)
      - Divorced: 799lbs/inch (140N/mm)
- A90 / A91 GR Supra:
  - FRS – Fast Road Spec:
    - Front: 343lbs/inch (60N/mm)
    - Rear: 799lbs/inch (140N/mm)
  - TDS – Track Day Spec:
    - Front: 457lbs/inch (80N/mm)
    - Rear: 913lbs/inch (160N/mm)

Applications

BMW Z4 M40i: G29 | 2019-2026
BMW Z4 sDrive20i: G29 | 2019-2026
BMW Z4 sDrive30i: G29 | 2019-2026
Toyota GR Supra: A90, A91, MK5 | 2020-2026

Other Suspension Kits for G29 Z4 / A9x GR Supra

NTR-R1 Coilover Kit
NTR-R1 Coilover Kit w/ Standalone FAL (A90 / A91 GR Supra only)
NTR-R3 Coilover Kit w/ Standalone FAL (A90 / A91 GR Supra only)
elec-TRON R1 Coilover Kit
elec-TRON R1 Coilover Kit w/ Standalone FAL (A90 / A91 GR Supra only)
elec-TRON R3 Coilover Kit
elec-TRON R3 Coilover Kit w/ Standalone FAL (A90 / A91 GR Supra only)

Notes

Compatible on 2.0L and 3.0L GR Supra models
If your Z4 or GR Supra is equipped with electronic damping, the Nitron Electronic Damping Delete Kit is required when fitting a non-electronic coilover kit to prevent fault codes and warning lights
Custom spring rates also available, please contact us directly here for more information or for a consultation on custom rates
Images used for illustration purposes only. Specific details, finishes and end fittings may differ from that shown.

Frequently Asked Questions

What is the practical difference between the piggyback and hose-mounted reservoir options on the A9x GR Supra NTR-R3? The piggyback reservoir mounts directly to the shock body, keeping the unit compact and self-contained. The hose-mounted reservoir connects via a separate hose, allowing it to be positioned away from the shock body where space or heat management requires it. On the GR Supra, both options are available at the front; the rear runs hose-mounted only. The choice generally comes down to packaging requirements and how the car is being built.
How does 3-way independent adjustment differ from the combined adjustment on the NTR-R1? The NTR-R1 uses a single adjuster controlling compression and rebound together. The Nitron NTR-R3 coilover separates high speed compression, low speed compression, and rebound into three independent circuits, each with its own adjustment range. That separation gives engineers the ability to tune each damping characteristic on its own terms rather than making compromises across the range with a single control.
Can the NTR-R3 be serviced and revalved? Yes. Every Nitron NTR-R3 coilover kit is fully serviceable and built to be rebuilt. Seals, oil, shim stacks, and spring rates can all be refreshed or changed independently, and the modular construction means individual dampers can be sent back without pulling the whole kit. For a car in regular track use, that serviceability is what makes the R3 a long-term investment rather than a consumable.
Is the NTR-R3 a significant step up from the NTR-R1 in terms of installation complexity? The hardware is more involved given the external reservoirs and independent adjustment circuits, but the installation process follows the same principles as any coilover fitment. The hose-mounted reservoirs on the rear require positioning during install, and the three adjustment knobs need to be set before the car goes back on the road, but neither adds meaningful complexity for anyone with coilover installation experience. The bigger difference is in setup depth once the car is on the ground.

About Nitron Suspension

Nitron Suspension has been at the forefront of precision suspension engineering since 1998, founded by Guy Evans with the goal of building high-performance shocks for enthusiasts and professionals alike. Over 200 dealers now carry Nitron products across Europe, Asia, the US, Australasia, and Africa. In 2008, the company moved into a dedicated facility in the UK’s Motorsport Valley, adding dynamometers, 5-axis CNC machines, and 3D CAD capabilities to support both growing demand and continued product development. A second expansion came in 2023 with a new office in Murrieta, California. The team behind every Nitron product draws from deep backgrounds in machining, materials technology, hydraulics, bike engineering, and F1 racing, with many engineers bringing firsthand experience as competitive drivers and riders. That depth of knowledge across both the technical and competitive sides of motorsport shapes every product Nitron develops.

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Nitron NTR-R3 Coilover Kit for G29 BMW Z4 / A9x Toyota GR Supra [NTCTO013R3]

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