Engine Bolts / Studs

- 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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
SET OF 12

Fits:
- 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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
Click 'Zoom in' for large parts diagram
Diagram ref no 20.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610418059
The product you are viewing cross references to these numbers
This kit is comprised of the following items:


- 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 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- 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 2007-09
- Porsche 997 MK1 GT2 2007-09
- Porsche 997 MKII GT3 2010-11
- Porsche 997 MKII Turbo 2010-13
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08

Fits:
Porsche 986 Boxster 1997-05
Porsche 987.1 Boxster 2005-08
Porsche 987.1 Cayman 2006-08
Porsche 996 Carrera 3.6L 2001-05 (9603)
Porsche 997.1 Carrera 3.6L / 3.8L 2005-08
Porsche 997.1 Turbo 2007-09
Porsche 997.2 Turbo 2010-13
Porsche 997 GT3 2007-11
Click 'Zoom in' for large parts diagram.
Diagram ref no 12
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
98710525401
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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
Priced Each - 14 required.

Fits:
Porsche 986 Boxster / Boxster S 1997-04
Porsche 987 Boxster / Boxster S 2005-08
Porsche 987C Cayman / Cayman S 2006-08
Porsche 996 Carrera 3.4L/3.6L 1998-04
Porsche 997.1 Carrera 3.6L/3.8L 2005-08
Click 'Zoom in' for large parts diagram.
Diagram ref no 16
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610111562
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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
SET OF 12

Fits:
Porsche 986 Boxster 2.7L / S 3.4L 2003-04
Porsche 987 Boxster 2005-08
Porsche 987C Cayman 2005-08
Porsche 996 C2 / C4 / C4S 2002-05
Porsche 997 Carrera 2005-08
Click 'Zoom in' for large parts diagram
Diagram ref no 20.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610418059
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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
24 Bolts Per Engine. Price is for EACH.

Fits:
Porsche 986 Boxster 2.7L / S 3.4L 2003-04
Porsche 987 Boxster 2005-08
Porsche 987C Cayman 2005-08
Porsche 996 C2 / C4 / C4S 2002-05
Porsche 997 Carrera 2005-08
Click 'Zoom in' for large parts diagram
Diagram ref no 20.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610418059
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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
24 Bolts Per Engine. Price is for EACH.

Fits:
Porsche 986 Boxster 2.7L / S 3.4L 2003-04
Porsche 987 Boxster 2005-08
Porsche 987C Cayman 2005-08
Porsche 996 C2 / C4 / C4S 2002-05
Porsche 997 Carrera 2005-08
Click 'Zoom in' for large parts diagram
Diagram ref no 20.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610418059
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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
SET OF 24 head studs, washers & nuts.

Fits:
Porsche 986 Boxster 2.7L / S 3.4L 2003-04
Porsche 987 Boxster 2005-08
Porsche 987C Cayman 2005-08
Porsche 996 C2 / C4 / C4S 2002-05
Porsche 997 Carrera 2005-08
Click 'Zoom in' for large parts diagram
Diagram ref no 20.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610418059
The product you are viewing cross references to these numbers



Precision Engine Bolts & Studs – Strength, Accuracy, and Reliability for Porsche Engines
Engine bolts and studs are the unsung heroes of your Porsche’s powerplant — small but vital components that ensure structural integrity under extreme stress. From securing cylinder heads and connecting rods to fastening crankcases and manifolds, every fastener must deliver uncompromising strength, precision, and clamping force to maintain your engine’s performance and reliability.
At Design911, we offer a comprehensive selection of standard and high-performance bolts, studs, nuts, and fasteners designed specifically for Porsche engines. Each high performance component is precision-engineered from high-tensile steel, titanium, or ARP-grade alloy, delivering exceptional resistance to heat, vibration, and torque fatigue.
Whether you’re rebuilding a classic air-cooled 911 or tuning a modern GT model, our manufacturer-quality fasteners guarantee secure fitment, consistent torque retention, and long-term durability.
What Do Engine Bolts and Studs Do?
Engine bolts and studs hold critical components together under immense pressure. They maintain precise torque and tension, ensuring the engine block, heads, and internal assemblies remain perfectly sealed and aligned.
Core Functions:
- Provide
secure clamping force for key engine assemblies (head, crankcase,
rods, etc.).
- Maintain
torque integrity under thermal expansion and vibration.
- Prevent
component movement, preserving internal clearances and sealing
surfaces.
- Support rebuild precision, allowing components to be serviced repeatedly without distortion.
Motorsport-grade fasteners are designed to handle repeated torque cycles and extreme stress, making them essential for both performance tuning and professional engine restoration.
Why Do Engine Bolts and Studs Fail?
Over time, fasteners experience stretching, fatigue, and corrosion from heat, oil exposure, and repeated torque cycles. Even the strongest bolts have a finite service life — and failing to replace them can lead to catastrophic engine damage.
Common Causes of Failure Include:
- Metal
fatigue or stretching from repeated torque applications.
- Corrosion
and oxidation, especially in humid or high-heat environments.
- Over-tightening
or under-torquing, compromising clamping force.
- Thread
wear or damage from improper installation or debris.
- Thermal cycling, weakening material structure over time.
Replacing aged or stressed bolts and studs during every rebuild or major service ensures your Porsche’s engine remains structurally sound and leak-free.
Why Replace with Precision-Engineered Bolts and Studs?
Upgrading to high-performance fasteners delivers the security and strength demanded by Porsche engines. Precision-engineered bolts and studs ensure consistent torque retention, improved reliability, and extended component life — especially in high-load or high-temperature conditions.
Key Benefits:
Superior
clamping strength and torque retention for critical assemblies.
High
fatigue resistance, preventing loosening or failure under pressure.
Improved
corrosion protection with zinc, nickel, or black oxide coatings.
Ideal
for rebuilds, upgrades, and performance tuning applications.
Precision-thread
machining ensures repeatable installation and alignment.
Available
in titanium and high-tensile steel for maximum strength-to-weight
ratio.
These bolts and studs provide the perfect balance of motorsport-level performance and road-going durability, keeping your Porsche engine secure mile after mile.
Highlights:
- Comprehensive
range of bolts, studs, and fasteners for Porsche engines.
- Manufactured from ARP-grade steel, titanium, or high-tensile alloy.
- Precision-machined
threads for perfect alignment and consistent torque.
- Improved resistance to heat, corrosion, and vibration.
- Essential for rebuilds, tuning, and restoration projects.
- Designed for air-cooled and water-cooled Porsche engines.