Rear Lower Control Arms for Porsche Boxster/Cayman 987
Brand : SPL Parts
- Part Number:
- SPL RLCA 987 V2
The SPL Rear Lower Control Arm Kit (RLCAK) significantly improves rear mechanical grip, provides greater stability under hard braking and acceleration, and precise feedback on what the rear is doing on turn-in and on limit. 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 camber loss, bumpsteer, and vague feedback that occur due to bushing deflection.
The kit enables adjustable track width, camber, rear roll center, and anti-squat for a deeper customization of the rear suspension geometry to better suit your driving preferences and adapt to changes in tracks, aero loading, tires, and more.
Technical
Camber Adjustment
Increase Camber for More Peak Lateral Grip
One of the biggest improvements to rear cornering grip you can make is adding more negative camber. This also will significantly improve track event tire life by reducing heavy wear on the outer portion of the tread that occurs when there's insufficient camber angle relative to body roll.
Rear Roll Center Adjustment
Reduce Body Roll with Geometry not Spring Rate
Roll center is the imaginary point that the chassis rolls about during cornering. The distance between the roll center and the center of gravity (front-view, vertical) is essentially the amount of leverage the chassis has to produce roll.
When you lower your Porsche the roll center drops further than the center of gravity, resulting in a larger roll moment (force). Using the roll center correction spacers to correct the angle of the rear lower control arm brings the roll center back up, resulting in less body roll at the same spring rate and less tendency to oversteer with fast transitions.
With the front and rear SPL kits, you can adjust the pitch of the roll axis which can have a significant effect on the car's handling behavior with respect to over and understeer, especially through esses.
Benefits
- Adjustable Rear Camber and Roll Center
- Lightweight: 2.85 lbs (1.29 kg) per Side
- Improved Rear Grip and Tire Wear on Track
- Precise Rotation and Steering Feel from Eliminating Bushing Deflection
- Greater Adaptability for Wheel/Tire Clearance
Materials
- 6061-T6 Billet Aluminum Arms and Clevis (Anodized Black)
- 6061-T6 Aluminum Spacers and 360° Clamps
- 4140 Chromoly Steel Double Adjuster (Electroless Nickel Plated)
- 4340 Chromoly Steel Studs (Heat-treated)
- Class 10.9 Metric Hardware / SAE Grade 8 Imperial Hardware
- Ti-6Al-4V Titanium 1/4"-20 Socket Head Allen Screws (Anodized Blue)
Noise, Vibration, and Harshness (NVH)
The rear lower control arms are an important part of mitigating NVH. By eliminating all bushing deflection the rear suspension will transmit more road noise, felt energy from bumps, and can increase tramlining in some cases. However, the reduction of bushing bind and reduced friction will improve ride quality over smoother roads and allow the shock to work more effectively over moderate bumps.
Tire choice, tire pressure, spring rates, and shock quality will have significant influence on ride quality as well. For daily driving, felt energy and noise can be reduced moderately by running a more compliant tire, either through reduced pressure (suitable for the load and tire) and/or taller or softer sidewalls, as well as optimized compression dampening on a quality shock.
Most drivers will find the NVH to be present and tolerable, similar to an OEM GT3 or GT4.
Applications
2005 - 2012 Porsche Boxster, Boxster S, Boxster Spyder, Boxster Spyder RS (987)
2005 - 2012 Porsche Cayman, Cayman S, Cayman R (987)
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
Occassionally, 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.
Replaces OEM Part Number(s)
This is a list of known OEM part numbers. OEMs constantly make changes to part numbers due to part updates, suppliers, etc so this may not be a complete list.
997 341 053 01
997 341 053 02
997 341 053 03
