Audi RS4 B8 Piston With Connecting Rod 4.2 FSI CFSA Petrol R079C 07L198401D

Audi RS4 B8 Piston With Connecting Rod 4.2 FSI CFSA Petrol is an original component from the Pistons and rings group, designed for high-performance petrol engines. Thanks to its factory geometry and precise fit for the CFSA unit, it ensures the consistency of the crank-piston system and stable combustion parameters in the 4.2 FSI sports engine.

Specifications and technical data

• SKU: 07L198401D
• Mark: Audi
• Condition: Used
• OEM Part Number: 07L198401D
• Substitutable numbers: 07L198401D, 07L 198 401 D, R079C
• Fuel type: Petrol
• Part type: Piston
• Category: Pistons & Rings

Purpose and function in the 4.2 FSI engine

The presented piston with connecting rod operates in the petrol engine as a key component transferring the energy of the mixture combustion to the crankshaft. In the 4.2 FSI CFSA unit, it is responsible for:

• maintaining proper compression in the cylinder,
• stable piston guidance in the sleeve at high RPMs,
• precise transfer of forces to the connecting rod and further to the crankshaft,
• maintaining power and torque characteristics in accordance with the manufacturer's specifications. By maintaining the original design, this component allows for the preservation of factory engine performance and repeatability of parameters across the entire rev range.

Advantages of using an original Audi piston with connecting rod

Using an original piston with connecting rod in a 4.2 FSI engine provides a number of practical service and operational benefits:

• Factory fit – dimensional and material compatibility with other components of the crank-piston system is maintained.
• Consistent operation in a petrol engine – the component is designed specifically for petrol-powered units, which promotes proper combustion.
• Simplified diagnostics and installation – the mechanic works with a known, serial design, which shortens repair time and reduces the risk of assembly issues.
• Possibility of replacing a single cylinder – in case of damage to one piston-connecting rod set, operating parameters can be restored without the need to interfere with the entire set.

Characteristics of the used component

The offered piston with connecting rod comes from dismantling and is a used component, which allows for economical engine repair while maintaining the original manufacturer's specifications. This type of component is particularly attractive in the case of:

• overhauls of units with high costs of new parts,
• repairs of vehicles used intensively, where the cost/effect ratio matters,
• restoring engine efficiency after local damage to a single cylinder. Choosing a used OEM component allows you to keep the engine construction at the factory standard, without the need to use replacements with uncertain parameters.

Integration with the crank-piston system and service application

The piston with connecting rod from the Audi RS4 B8 works with the stock crankshaft, bearings, and cylinder head of the 4.2 FSI CFSA unit. In workshop practice, it proves effective both for partial overhauls and for engine rebuilding after a mechanical failure. Thanks to the original design:

• the proper mass of moving parts is maintained,
• the balance of the crank system is preserved,
• the risk of additional vibrations and noise is reduced. This solution is recommended for users who want to restore the efficiency of the power unit while maintaining the performance character typical of the sports RS4 B8 model. If you are planning a comprehensive repair or upgrade of the engine area in your Audi and need other elements from the same group, such as pistons, rings, or complete piston sets, check the available parts in the Audi Pistons and rings category. To better plan the engine overhaul and shorten the car's downtime at the service center, it is worth reading the guide on the impact of the availability of used OEM parts on the repair process – this is discussed in detail in the article Availability of car parts off the shelf vs. repair time – how used OEM parts shorten the stay in the workshop?.