De-Cambered Ball Joint For A-Arm Set - (FI 18). Porsche 911 RS 1974-89

De-Cambered Ball Joint For A-Arm Set - (FI 18).
Upgrade your front suspension geometry with the De-Cambered Ball Joint Set (FI-18). These offset ball joints are engineered to provide an inbuilt additional 3mm negative camber bias, improving front-end grip and cornering response without the need for major suspension modifications.  
Sold As A Set.
x2 Sets Required Per Car.

Fits:

• Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
• Porsche 911 1978-1983 3.0L / SC
• Porsche 911 1984-1986 3.2L
• Porsche 911 1987-1989 3.2L G50
• Porsche 911 1975-1977 3.0L Turbo (930)
• Porsche 911 1978-1989 3.3L Turbo (930)

(For Cars Fitted With RS Type Suspension)

What This Product Does:

• Increases Negative Camber “by Default” - Because the stud is offset outward, the wheel gets a small amount of negative camber without requiring changes at the top strut mount. This helps maintain better contact patch under cornering forces.
• Counters Camber Loss Under Load - In cornering, body roll or suspension compression tends to reduce negative camber (i.e. flatten the tire). The de-cambered joint helps offset that loss so the inside tire stays more planted.
  
• Improves Handling Stability and Turn-In - With more negative camber under load, the front end grips better, reducing understeer and making turn-in sharper.
  
• Mild Track / Performance Tuning Without Major Mods - Rather than needing to retrofit adjustable camber plates or change strut towers, this joint gives a modest camber “boost” in a bolt-on manner.
  
• Retains Full Ball Joint Functionality - It still allows articulation (steering, suspension travel) like a normal ball joint — the offset is only in its alignment, not in its motion.
  
  

Symptoms Of Worn Or Failing Ball Joint:

• Knocking or Clunking Noises - A dull knock from the front suspension, particularly over bumps or while turning, often indicates play in the ball joint.
  
• Uneven or Excessive Tire Wear - Worn joints allow uncontrolled camber and toe changes, wearing the inside or outside edges of the front tires.
  
• Loose or Wandering Steering - When the ball joint develops play, the steering feels vague or “floaty” — the car no longer holds a consistent line through corners.
  
• Vibration or Shimmy at Speed - Free play in the joint can cause steering wheel vibration, particularly over rough surfaces.
  
• Visible Wear or Damage - Torn dust boots, leaking grease, or excessive movement when inspected during service are clear signs the joints need replacing.
  
• Inconsistent Handling Under Load - The car may feel unstable mid-corner or react unpredictably to bumps due to geometry shifts caused by worn ball joints.
  
  

Why Replacement / Upgrading Matters:

• Restores Safety & Structural Integrity - The ball joint supports the front suspension load. A failure can cause complete loss of steering control.
  
• Maintains Proper Wheel Alignment - Fresh joints eliminate unwanted camber/toe drift and keep tires correctly aligned under all loads.
  
• Improves Steering Precision - Tight, new ball joints restore that crisp Porsche steering feel and predictable handling
  
• Enhances Cornering Grip - The de-cambered design adds built-in negative camber, improving tire contact and front-end grip through corners.
  
• Prevents Secondary Wear - Worn joints increase stress on tires, control arms, and suspension bushings — leading to expensive downstream repairs.
  
• Perfect for Performance & Track Use - The offset camber geometry helps maintain optimal contact patches during high lateral loads, reducing understeer and improving lap-to-lap consistency.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

90134104704

The product you are viewing cross references to these numbers