Standard Alternator / Genarator
As the heart of your charging system, this alternator supplies electrical power to all onboard systems and recharges the battery while the engine runs. It ensures reliable operation of lights, infotainment, climate control, and engine electronics under demanding loads.
Fits:
For cars with Tiptronic transmission (I249)
Porsche 987.1 Boxster 2007-08
Porsche 987C.1 Cayman 2007-08
Porsche 997.1 Carrera 2007-09
Porsche 997.1 Turbo 2007-09
Porsche 997 GT3 2010-11
Plug type

Diagram ref no 20
A failing alternator can cause low voltage, battery drain, flickering lights, or total electrical failure. Upgrading with an OE Match unit restores consistent charging performance and avoids costly roadside failures.
- Fits Porsche 911, Boxster, and Cayman models (verify engine compatibility)
- 150-amp output for stable electrical and charging performance
- Fixed-type pulley design for direct bolt-on installation
- Matches factory alternator dimensions, connections, and output curve
- Restores optimal charging to power all vehicle systems
- Built with high-quality bearings, windings, and voltage regulators for longevity
- Tested for durability and consistent voltage under high-load operation
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99760302204
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08

Fits:
For cars with Tiptronic transmission (I249) and Manual transmission (I480/481)
Porsche 987.1 Boxster 2007-08
Porsche 987C.1 Cayman 2007-08
Porsche 997.1 Carrera 2007-09
Porsche 997.1 Turbo 2007-09
Porsche 997 GT3 2010-11
Plug type

Diagram ref no 20
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99760302205
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08

Reconditioned alternator. For cars year 2007 onwards. (with Freewheel pulley)
Fits:
For cars with Tiptronic transmission (I249) and Manual transmission (I480/481)
Porsche 987.1 Boxster 2007-08
Porsche 987C.1 Cayman 2007-08
Porsche 997.1 Carrera 2007-09
Porsche 997.1 Turbo 2007-09
Porsche 997 GT3 2010-11
Plug type

Diagram ref no 20
Reconditioned Alternators are sold on a exchange basis, A surcharge of £100.00 will be held and then refunded when the old one is returned.
- The surcharge for this reconditioned part will be refunded when the exchange unit is received and approved by us and the relevant manufacturer.
- Please note, surcharge refunds often take an average of 6 to 8 weeks to be approved by the manufacturer.
- Acceptance of the exchange part is at the manufacturer's discretion, based on the part being fit for reconditioning.
- All surcharges and exchanges are subject to our terms and conditions.
PLEASE NOTE:
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99760302205
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
Fits:
For cars with Tiptronic transmission (I249) and Manual transmission (I480/481)
Porsche 987.1 Boxster 2007-08
Porsche 987C.1 Cayman 2007-08
Porsche 997.1 Carrera 2007-09
Porsche 997.1 Turbo 2007-09
Porsche 997 GT3 2010-11
Plug type

Diagram ref no 20
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99760302205
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08

Fits:
Porsche 997 GT2 2007-09
Diagram ref no 27
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99760703404
The product you are viewing cross references to these numbers
- Porsche 997 MK1 GT2 2007-09
Standard Output Alternators – Reliable Power Generation for Porsche Vehicles
Standard output alternators are a vital component in your Porsche’s electrical and charging system. They generate the electricity required to power essential systems such as lighting, ignition, infotainment, and battery charging. A dependable alternator ensures your vehicle maintains optimal voltage output, supporting both performance and everyday drivability.
At Design911, we offer a complete range of genuine and manufacturer-quality standard output alternators for Porsche models including 911, Boxster, Cayman, Cayenne, Macan, Panamera and transaxle models. Each alternator is precision-engineered for efficient charging, quiet operation, and long-term durability, delivering the performance your Porsche deserves.
What Do Standard Output Alternators Do?
Alternators play a crucial role in your Porsche’s electrical
system. Their main functions include:
- Generating
electrical power to run engine and vehicle electronics.
- Charging
the battery while the engine is running.
- Regulating
voltage output for consistent electrical performance.
- Powering accessories such as headlights, fans, and infotainment systems.
Standard output alternators provide reliable current for road use, ensuring steady voltage supply without overloading your vehicle’s electrical components.
Why Do Alternators Fail?
Alternators operate under high mechanical and electrical
loads, so over time they can wear or fail due to age, heat, and vibration.
Common causes include:
- Worn
bearings or brushes reducing output efficiency.
- Faulty
voltage regulators causing under- or overcharging.
- Corrosion
or oxidation in internal electrical connections.
- Loose
or slipping drive belts affecting alternator speed.
- Exposure to moisture, oil, or debris damaging internal components.
Symptoms of alternator failure include dimming headlights, electrical malfunctions, dead batteries, or dashboard battery warning lights.
Why Replace a Faulty
Alternator?
A failing alternator can cause serious electrical problems,
leaving you with a drained battery or stranded vehicle. Replacing a weak or
damaged alternator restores proper charging function, ensuring smooth
performance and reliability.
Benefits of replacement include:
- Consistent battery charging and voltage stability.
- Improved performance of all vehicle electronics.
- Prevention of battery drain and starting issues.
- Quiet, efficient, manufacturer-quality alternator operation.
Each alternator in this range is made using high-grade materials and precision-balanced components, ensuring dependable performance, low noise, and strong output for both standard and high-demand driving conditions.
1. What are the signs of a failing alternator in a
Porsche?
Common signs of a bad alternator include dimming
headlights, battery warning lights on the dashboard, slow or
failed engine starts, and unusual whining noises from the engine
bay. You might also notice intermittent electrical issues or a drained
battery, which often indicates the alternator is no longer charging
efficiently.
2. How long should a Porsche alternator last?
A well-maintained alternator in most Porsche models
typically lasts between 60,000 and 100,000 miles, depending on driving
conditions and electrical demand. Regular maintenance of belts and battery
connections helps extend alternator lifespan. If your vehicle is frequently
driven in stop-start traffic or harsh environments, periodic inspections are
recommended.
3. Can I drive my Porsche with a failing alternator?
Driving with a failing alternator is not recommended.
Once the alternator stops generating power, your Porsche will rely solely on
the battery — which can drain quickly. This can lead to engine stalling,
loss of power steering, or total electrical failure. To prevent further
damage, it’s best to replace the alternator as soon as symptoms appear.
4. What causes alternator failure in Porsche vehicles?
Alternator failure can be caused by worn bearings or
brushes, corrosion in electrical connections, a damaged voltage
regulator, or contaminants like oil or moisture entering the
alternator housing. Over time, high temperatures and belt tension can
also reduce efficiency or cause internal damage. Regular servicing helps
identify these issues early.