Rear Lower Trailing Arm Spherical Bushing Kit for Porsche 991 GT3
Brand : SPL Parts
- Part Number:
- SPL RTRB 991 GT3
The SPL rear lower trailing control arm spherical bushing kit (RTRB 991 GT3) replaces the OEM rear lower trailing control arm bushings with spherical bushings to greatly improve the precision of the rear suspension. The use of PTFE-lined, F1-fit FK USA spherical bushings eliminates OEM rubber bushing deflection and bind, allowing the suspension to freely articulate without undampened rubber "spring" forces, while also preventing unwanted geometry changes and vague feedback that occur due to bushing deflection.
Technical
Zero Bushing Deflection
Precision Bump Geometry, Every Corner
Compliant OEM bushings deflect under load to improve NVH and influence the handling behavior at the limit. This elastokinematic tuning has to meet the diverse goals set by the vehicle's design requirements, including NVH, component cost, service life, and more.
Our spherical bushing kit is designed for those who prioritize performance and handling precision. This is achieved by eliminating bushing deflection and the resulting compliance steer effects, which makes driving more predictable, and simplifies the kinematic setup in the rear to make dialing in the car that much easier.
Reduce Wheel Hop
Keep the Wheel Planted
Sudden acceleration from launch control, low gear changes, sharp braking or even ABS engagement can initiate wheel hop in some conditions. The OEM rubber bushings contribute by deflecting under load, which allows the wheel to move and enter into a destructive wheel hop cycle. SPL spherical bushings eliminate the deflection in the rear lower arm and help maintain consistent tire contact.
Prevent Bumpsteer
Predictable Handling Characteristics
The rear lower trailing control arms locate the wheel longitudinally (front to back). Under heavy acceleration loads from engine torque, track curbing, and/or braking torque, the OEM rubber bushings deflect, causing changes to the kinematics that can result in bumpsteer. Switching to spherical bushings eliminates this deflection, which retains predictable handling characteristics and prevents instability due to bumpsteer.
Eliminates Bushing Bind
Less Bounce, More Control, Greater Simplicity
Bushing bind is a significant source of resistance to suspension travel and acts as a rubber torsion spring that resists compression and rebound. This force is poorly controlled by the damper and complicates the suspension model. PTFE-lined spherical bearings have extremely low friction and allow the spring and damper to work more effectively through the entire sweep of the suspension. This delivers a more linear, controlled, and predictable driving experience.
Benefits
- Improved Handling Precision & Stability
- Reduced Wheel Hop
- Near Zero Sliding Friction
- Sharpened Rear Suspension Response and Feedback
Materials
- 6061-T6 Billet Aluminum Bushing Shells
- FK USA PTFE-lined Spherical Bearings
- 6061-T6 Aluminum Spacers
Noise, Vibration, and Harshness (NVH)
Replacing the OEM rear lower trailing control arm bushings with SPL sphericals will add a small to moderate amount of NVH in some driving situations. This particular arm is active in the longitudinal direction, so it is more susceptible to NVH than other bushings. Compared to other sources of NVH, the contribution from the sphericals is low to moderate, and well tolerated.
Applications
2014 - 2019 Porsche 911 GT3 / GT3RS / R (991)
ADDITIONAL FITMENT INFO
WILL THIS FIT A ...
We limit the above applications to known fitments from testing and research. If you're unsure if this is the proper part for your application, send us an email.
THIS SHOULD FIT MY CAR
Occasionally, parts will fit other vehicles not listed above. If you believe, or know, this part will fit your vehicle, send us an email and we'll work with you to confirm proper fitment.
