Engine piston. Porsche 997.2 3.8L / 991.1 3.8L / 981 Boxster Spyder / 981C Cayman GT4  ❭  9A110393800

Engine piston.
This genuine Porsche Engine Piston is a core internal engine part for high-performance 3.8 L Porsche engines found in 997.2, 991.1, 981 Boxster Spyder, and 981C Cayman GT4 models. As a complete Porsche-specified piston, it ensures correct combustion sealing, friction characteristics, thermal resilience, and integration with OE rings and rods - preserving factory performance, durability, and engine dynamics.
Sold each, 6 required per vehicle.

Fits:
Porsche 997.2 Carrera 4 / 4S / 4GTS 3.8L 2009 - 2012
* engine code: A101

Porsche 991.1 Carrera 4 / 4S / 4GTS 3.8L 2012 - 2016
 * engine code: A103
 * cars without Compression variant   (PR:-145) 

Porsche 981 Boxster Spyder 3.8L 2016
Porsche 981C Cayman GT4 3.8L 2016

Diagram ref no 1

An engine piston is a critical internal combustion engine component that reciprocates within the engine’s cylinder bore. Its primary role is to convert the expanding gas forces created by combustion into mechanical motion. When fuel and air ignite in the combustion chamber, the piston is driven downward, transmitting force through the connecting rod to the crankshaft - ultimately generating engine power. The piston also helps seal the combustion chamber, control oil consumption, and withstand extreme temperatures and pressures during operation.

Functions & Technical Role:
•  Combustion pressure handling: Converts the force of combustion into linear piston movement
•  Sealing the chamber: Works with piston rings to maintain compression and prevent blow-by
•  Heat resistance: Made from high-strength aluminium alloy to endure extreme engine temperatures
•  Oil control: Cooperates with rings and skirt design to manage oil lubrication
•  Precision fit: Porsche-specified dimensions and surface finishes reduce friction and improve longevity

Fitment / Position on Car
•  Installed on: Inside the engine block’s cylinder bores
•  Location: One per cylinder; typically 6 pistons required for a complete 3.8 L flat-six engine
•  Orientation: Works with piston rings, wrist pin, and connecting rod to form the bottom of the combustion chamber

Pistons operate at the heart of the combustion process under extreme heat and pressure. Using a genuine Porsche OE piston means you’re getting:
•  Exact metallurgical specification matched to the engine’s operating envelope
•  Precision machining tolerances for optimal clearances and minimal friction
•  Verified durability and fatigue resistance for high RPM use
•  Factory-matching to rings and skirts for combustion sealing and minimal blow-by

Genuine OE pistons ensure reliability and longevity.

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9A110393800

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