Audi RS4 B8 RS5 8T Crankshaft Timing Belt Pulley 4.2 Petrol CFSA 079105251AL

Audi RS4 B8 RS5 8T Crankshaft Timing Belt Pulley 4.2 Petrol CFSA is an original part from the Crankshafts group, designed for 4.2 CFSA petrol engines in Audi RS4 B8 and RS5 8T sports models. This used OEM part ensures proper cooperation with the crankshaft, stable operation of engine accessories, and maintenance of the factory parameters of the powertrain.

Specifications and technical data

• SKU: 079105251AL
• Mark: Audi
• Condition: Used
• OEM Part Number: 079105251AL
• Substitutable numbers: 079105251AL, 079 105 251 AL
• Fuel type: Petrol
• Category: Crankshafts

Purpose and function of the pulley

The crankshaft pulley in the 4.2 CFSA petrol engine is responsible for transferring drive from the crankshaft to engine accessories, such as components of the belt-driven system. A properly selected pulley reduces crankshaft torsional vibrations, supports smooth operation of the powertrain, and helps maintain stable RPM across the entire engine operating range.

In the case of powerful V8 units used in the RS4 B8 and RS5 8T, the correct selection of this component is important for the refinement, durability of the crankshaft, and other components cooperating with the belt drive. Using an original pulley from the same design group allows for maintaining the parameters specified by the manufacturer.

Benefits of using an original pulley

Using an original crankshaft pulley in the CFSA engine ensures:

• maintenance of factory geometry and alignment relative to the crankshaft,
• proper routing of the accessory belt and stable tension during operation,
• adequate damping of vibrations resulting from the V8 engine characteristics,
• consistency with other drivetrain components intended for the RS version.

Thanks to this, the engine's drive system operates under conditions close to factory specifications, which promotes the durability of the crankshaft, bearings, and belt-driven accessories. The used OEM part is a good solution for repairs where maintaining the original specification is crucial, without the need to use replacements with uncertain parameters.

Application in the 4.2 CFSA petrol engine

The presented pulley is intended for petrol-powered engines with the CFSA code, used in Audi RS4 B8 and RS5 8T sports models. The design of the component is adapted to the loads and characteristics of the high-performance 4.2 engine, which allows for safe operation in a wide range of RPM, typical for naturally aspirated engines with a sporty purpose.

Selecting a pulley that meets this specification is particularly important during repairs after a drivetrain failure, accessory belt replacement, or service work related to the crankshaft. Consistency with the original design reduces the risk of improper accessory alignment and accelerated wear of cooperating components.

Part condition and installation aspects

The offered crankshaft pulley is a used part, sourced from dismantling, which allows for an economical repair while maintaining the manufacturer's original specification. Before installation, it is recommended to perform a standard verification of the working surfaces, mounting seats, and cooperating drivetrain components to ensure proper seating on the shaft and correct belt operation.

When replacing the pulley, it is worth paying attention to:

• the condition of the contact surface with the crankshaft,
• the absence of mechanical damage on the working circumference,
• proper tightening in accordance with the service procedure for the given model.

Technical support and additional information

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 other pulleys, vibration damping elements, or related crankshaft components, check the available parts in the Audi Crankshafts category.

When working on the powertrain, it is also worth paying attention to the condition of the cooling system, which has a direct impact on the durability of the crankshaft and cooperating components. More practical information on the impact of engine operating temperature on its lifespan can be found in the article Engine cooling system – overheating, repair, and used radiators.