Porsche Alternator (14V / 90 Amp) – 911/930 (1984–1989) 911-603-120-05-OEM | OEM Engine Charging System

Ensure consistent power and reliability in your classic Porsche with the Porsche Alternator (14V / 90 Amp) – 911-603-120-05. Designed for Porsche 911 and 930 models from 1984 to 1989, this OEM alternator delivers stable voltage output and efficient charging performance for air-cooled engines.

Built with precision-engineered copper windings and a durable aluminum casing, it ensures optimal electrical performance under demanding conditions. Whether restoring or maintaining your 911, this alternator provides dependable current flow to support ignition, lighting, and all electrical components while preserving Porsche’s factory performance standards.

Key Features

• OEM Porsche Quality – Engineered to Porsche specifications for perfect fit and reliable charging performance

• 14V / 90 Amp Output – Provides consistent electrical power for ignition, lighting, and accessories

• Durable Aluminum Housing – Lightweight yet strong for heat dissipation and long-term dependability

• Precision Copper Windings – Ensures stable voltage and reduced energy loss during operation

• Direct Fit for Porsche 911 and 930 (1984–1989) – Easy installation with factory-style mounting and connectors

• Improves Electrical Efficiency – Maintains proper battery charge and system performance under all driving conditions

• Ideal for Restorations and Maintenance – Recommended for engine rebuilds, electrical system upgrades, or replacement of aging components

Frequently Asked Questions (FAQ)

1. What does the Porsche Alternator (911-603-120-05) do?
The alternator converts mechanical energy from the engine into electrical power to charge the battery and run the vehicle’s electrical systems.

2. Which Porsche models is this alternator compatible with?
This alternator fits Porsche 911 and 930 models produced between 1984 and 1989.

3. What are the symptoms of a failing alternator?
Common signs include dimming lights, weak battery performance, dashboard warning lights, or unusual noises from the engine bay.

4. Is this an OEM-quality alternator?
Yes, this alternator meets Porsche’s factory specifications for power output, durability, and fitment.

5. Should I replace the alternator during an engine rebuild?
Yes, replacing the alternator during a rebuild or major service ensures consistent voltage output and prevents electrical failures down the line.