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Control Arms Rear

Fits:
Porsche 986 Boxster
Porsche 987 Boxster / Cayman
Porsche 993
Porsche 996
Porsche 997
Product Description
Rennline's Eccentric lock kits replaces the factory Eccentric adjustment system which are commonly known to cause loss of alignment during track use. These locks allow you to securely anchor the subframe side of your adjustable links, and ensures that your alignment does not change under heavy load.
Sold as a pair this includes 2 bolts, 2 lock nuts, 4 washers and 4 eccentric locks.
993 - Can be used on upper control arms, and lower toe arms.
996/997/986/987 - Can be used on lower control arms and lower toe arms.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
S40
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005-08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Boxster 987 MKII 2.9L 2009-12
- Porsche Boxster S 987 MKII 3.4L 2009-12
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 996 GT3 RS 2003-04
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MK1 GT3 / GT3 RS 2007-09
- Porsche 997 MK1 GT2 2007-09
- Porsche 997 MKII Carrera C2 3.6L 2009-12
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C2S 3.8L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche 997 MKII GT3 / GT3 RS 2010-11
- Porsche 997 MKII Turbo 2010-13
- Porsche 997 MKII GT2 RS 2011-13
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12
- Porsche Cayman 2.7L 981 2013-16
- Porsche Cayman S / GTS 3.4L 981 2013-16
With no replacement bushes available from Porsche, these uprated Powerflex bushes provide a high-performance, durable, and cost-effective alternative to purchasing a complete arm.
Fits:
Porsche 993 Carrera 1994-98
Porsche 993 Carrera RS 1995-96
Porsche 993 Turbo 1995-98
Porsche 993 GT2 1996-98
Powerflex diagram ref. 13.
Sold as a set of two, these bushes are a direct replacement for the inner bush on part number 99333104301 - the rearmost control arm on the rear axle, which manages toe angle adjustment.
The Powerflex Range:
Road Series (Road & Fast Road) - POWERFLEX Road Series bushes improve your cars’ road holding and chassis performance by controlling the amount of unwanted flex in the suspension. This means the suspension is doing what it is supposed to. It means your tyres have greater contact with the road at all times, therefore, improving safety and performance. Correctly formulated polyurethane is as good if not better at noise, vibration and harshness suppression when compared to worn rubber. Our Road bushes offer Prolonged tyre life, Improved performance, Increase safety, and Greater cost-effectiveness.
Black Series (Track & Motorsport) - POWERFLEX Black Series bushes are manufactured using our Black 95 Shore A compound to provide maximum control of chassis geometry. They are designed for the Track, ready to Race and are engineered to be the best. This compound can be up to 80% more resistant to load than standard rubber and 25% stiffer than our purple performance material. If your requirements are purely for the ultimate in handling and chassis performance then Powerflex Black Series are unique, offering the most precise and accurate alignment for your chassis.
Heritage Collection (Classic & Restoration Use) - POWERFLEX Heritage Collection bushes are manufactured using modern-day materials with properties biased for the road. These dark grey coloured bushes will improve any collector’s car, whilst retaining the same standard appearance of a rubber bush. Our new range speaks to the growing demand for quality replacement parts that have an aesthetic in keeping with’ the look of the original part and restoration project as a whole whilst carrying all of the performance and longevity benefits offered by Powerflex’s unique blend of polyurethane. Going a step further than simply using the same material and durometer of hardness for all of our parts, each part location has its own shore designation to ensure improved suspension performance without discomfort or vibration, all of which ship in our new ‘Classic’ Dark Grey colour suitable for all road-based applications.
Powerflex Materials:
The materials used by Powerflex are colour coded to make them easily identifiable. Below explains the shore rating and their common uses.
Red 65A – Used for our Universal exhaust mounts and diesel engine mounts.
Yellow 70A – Mainly used for engine mounts, diff mounts and subframe mounts or areas where the bush needs a lot of movement and absorption.
Purple 80A – Our most common material. This is used in most areas of the suspension and provides the right mix between performance and compliance.
Black 95A – Our hardest material. This is used mostly for our Black Series range or in our Road Series where the vehicle’s standard suspension demands require us to use this hardness of material i.e. in areas of high load.
Grey* - Used specifically for our Heritage Collection. This can be any of the durometers mentioned but will always be the same as the equivalent part from our Road Series i.e. if it’s Purple 80A in our Road Series, it’d be Grey 80A in our Heritage Collection. On our Road Series and Heritage Collection kits, we can use a mix of all 4 of our materials. During the development stages, we test the original bush and see what the requirements are for strength and movement. At that point, we then decide which of our materials would be best suited. We don’t believe in a one material suits all rule. Manufacturers will do the same and will use different shore rubbers, however, it’s not as noticeable as all rubber bushes look visually similar.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
PFR57-913
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
With no replacement bushes available from Porsche, these uprated Powerflex bushes provide a high-performance, durable, and cost-effective alternative to purchasing a complete arm.
Fits:
Porsche 993 Carrera 1994-98
Porsche 993 Carrera RS 1995-96
Porsche 993 Turbo 1995-98
Porsche 993 GT2 1996-98
Powerflex diagram ref. 13.
Sold as a set of two, these bushes are a direct replacement for the inner bush on part number 99333104301 - the rearmost control arm on the rear axle, which manages toe angle adjustment.
The Powerflex Range:
Road Series (Road & Fast Road) - POWERFLEX Road Series bushes improve your cars’ road holding and chassis performance by controlling the amount of unwanted flex in the suspension. This means the suspension is doing what it is supposed to. It means your tyres have greater contact with the road at all times, therefore, improving safety and performance. Correctly formulated polyurethane is as good if not better at noise, vibration and harshness suppression when compared to worn rubber. Our Road bushes offer Prolonged tyre life, Improved performance, Increase safety, and Greater cost-effectiveness.
Black Series (Track & Motorsport) - POWERFLEX Black Series bushes are manufactured using our Black 95 Shore A compound to provide maximum control of chassis geometry. They are designed for the Track, ready to Race and are engineered to be the best. This compound can be up to 80% more resistant to load than standard rubber and 25% stiffer than our purple performance material. If your requirements are purely for the ultimate in handling and chassis performance then Powerflex Black Series are unique, offering the most precise and accurate alignment for your chassis.
Heritage Collection (Classic & Restoration Use) - POWERFLEX Heritage Collection bushes are manufactured using modern-day materials with properties biased for the road. These dark grey coloured bushes will improve any collector’s car, whilst retaining the same standard appearance of a rubber bush. Our new range speaks to the growing demand for quality replacement parts that have an aesthetic in keeping with’ the look of the original part and restoration project as a whole whilst carrying all of the performance and longevity benefits offered by Powerflex’s unique blend of polyurethane. Going a step further than simply using the same material and durometer of hardness for all of our parts, each part location has its own shore designation to ensure improved suspension performance without discomfort or vibration, all of which ship in our new ‘Classic’ Dark Grey colour suitable for all road-based applications.
Powerflex Materials:
The materials used by Powerflex are colour coded to make them easily identifiable. Below explains the shore rating and their common uses.
Red 65A – Used for our Universal exhaust mounts and diesel engine mounts.
Yellow 70A – Mainly used for engine mounts, diff mounts and subframe mounts or areas where the bush needs a lot of movement and absorption.
Purple 80A – Our most common material. This is used in most areas of the suspension and provides the right mix between performance and compliance.
Black 95A – Our hardest material. This is used mostly for our Black Series range or in our Road Series where the vehicle’s standard suspension demands require us to use this hardness of material i.e. in areas of high load.
Grey* - Used specifically for our Heritage Collection. This can be any of the durometers mentioned but will always be the same as the equivalent part from our Road Series i.e. if it’s Purple 80A in our Road Series, it’d be Grey 80A in our Heritage Collection. On our Road Series and Heritage Collection kits, we can use a mix of all 4 of our materials. During the development stages, we test the original bush and see what the requirements are for strength and movement. At that point, we then decide which of our materials would be best suited. We don’t believe in a one material suits all rule. Manufacturers will do the same and will use different shore rubbers, however, it’s not as noticeable as all rubber bushes look visually similar.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
PFR57-913BLK
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
With no replacement bushes available from Porsche, these uprated Powerflex bushes provide a high-performance, durable, and cost-effective alternative to purchasing a complete arm.
Fits:
Porsche 993 Carrera 1994-98
Porsche 993 Carrera RS 1995-96
Porsche 993 Turbo 1995-98
Porsche 993 GT2 1996-98
Powerflex diagram ref. 13.
Sold as a set of two, these bushes are a direct replacement for the inner bush on part number 99333104301 - the rearmost control arm on the rear axle, which manages toe angle adjustment.
The Powerflex Range:
Road Series (Road & Fast Road) - POWERFLEX Road Series bushes improve your cars’ road holding and chassis performance by controlling the amount of unwanted flex in the suspension. This means the suspension is doing what it is supposed to. It means your tyres have greater contact with the road at all times, therefore, improving safety and performance. Correctly formulated polyurethane is as good if not better at noise, vibration and harshness suppression when compared to worn rubber. Our Road bushes offer Prolonged tyre life, Improved performance, Increase safety, and Greater cost-effectiveness.
Black Series (Track & Motorsport) - POWERFLEX Black Series bushes are manufactured using our Black 95 Shore A compound to provide maximum control of chassis geometry. They are designed for the Track, ready to Race and are engineered to be the best. This compound can be up to 80% more resistant to load than standard rubber and 25% stiffer than our purple performance material. If your requirements are purely for the ultimate in handling and chassis performance then Powerflex Black Series are unique, offering the most precise and accurate alignment for your chassis.
Heritage Collection (Classic & Restoration Use) - POWERFLEX Heritage Collection bushes are manufactured using modern-day materials with properties biased for the road. These dark grey coloured bushes will improve any collector’s car, whilst retaining the same standard appearance of a rubber bush. Our new range speaks to the growing demand for quality replacement parts that have an aesthetic in keeping with’ the look of the original part and restoration project as a whole whilst carrying all of the performance and longevity benefits offered by Powerflex’s unique blend of polyurethane. Going a step further than simply using the same material and durometer of hardness for all of our parts, each part location has its own shore designation to ensure improved suspension performance without discomfort or vibration, all of which ship in our new ‘Classic’ Dark Grey colour suitable for all road-based applications.
Powerflex Materials:
The materials used by Powerflex are colour coded to make them easily identifiable. Below explains the shore rating and their common uses.
Red 65A – Used for our Universal exhaust mounts and diesel engine mounts.
Yellow 70A – Mainly used for engine mounts, diff mounts and subframe mounts or areas where the bush needs a lot of movement and absorption.
Purple 80A – Our most common material. This is used in most areas of the suspension and provides the right mix between performance and compliance.
Black 95A – Our hardest material. This is used mostly for our Black Series range or in our Road Series where the vehicle’s standard suspension demands require us to use this hardness of material i.e. in areas of high load.
Grey* - Used specifically for our Heritage Collection. This can be any of the durometers mentioned but will always be the same as the equivalent part from our Road Series i.e. if it’s Purple 80A in our Road Series, it’d be Grey 80A in our Heritage Collection. On our Road Series and Heritage Collection kits, we can use a mix of all 4 of our materials. During the development stages, we test the original bush and see what the requirements are for strength and movement. At that point, we then decide which of our materials would be best suited. We don’t believe in a one material suits all rule. Manufacturers will do the same and will use different shore rubbers, however, it’s not as noticeable as all rubber bushes look visually similar.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
PFR57-913H
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
Rear Control Arms (Coffin Arms) – Stability, Alignment and Rear-End Control
Rear control arms, commonly referred to as coffin arms, are critical suspension components responsible for controlling rear wheel alignment, stability and handling balance. Mounted between the rear hub and chassis, these arms manage camber and toe movement as the suspension compresses and extends, directly affecting traction, tyre wear and overall vehicle confidence.
At Design911, we supply OE replacement and performance rear coffin arms from trusted suspension manufacturers. Whether you are addressing worn factory components or upgrading for fast-road and track use, rear control arms play a vital role in maintaining predictable handling and restoring proper suspension geometry.
What Do Rear Control Arms (Coffin Arms) Do?
Rear control arms locate the rear wheels and guide their
movement through suspension travel. Their primary functions include:
- Maintaining correct rear wheel camber and toe
- Providing rear-end stability under acceleration and cornering
- Supporting predictable handling balance
- Reducing unwanted suspension flex
Because the rear suspension governs traction and stability, worn or flexing coffin arms can significantly affect handling feel and tyre life.
Why Upgrade or Replace Rear Coffin Arms?
Upgrading or replacing rear control arms offers:
- Restored rear suspension geometry and alignment accuracy
- Improved traction and stability during cornering
- Reduced uneven tyre wear
- Better feedback and control during spirited driving
Performance rear control arms may feature stronger materials, uprated bushes or adjustable geometry, allowing fine-tuning of rear suspension setup for performance driving or track use.
When Should You Replace Rear Control Arms?
Rear coffin arms should be replaced or upgraded when:
- Suspension bushes are cracked, worn or noisy
- Rear alignment cannot be set correctly
- Handling feels unstable or unpredictable
- Uneven rear tyre wear is present
- Performing a suspension refresh or performance upgrade
Replacing worn rear control arms helps restore factory handling characteristics and improves overall driving confidence.
At Design911, our rear control arms meet OE or performance standards, supporting both professional servicing and enthusiast upgrades.