Heating block off plate. Porsche 911/912/930 65-89  ❭  91121129700

Heating Block Off Plates (Pair)

Complete your engine restoration or heater system modification with this Heating Block Off Plate Kit, supplied as a pair. These plates provide a secure seal for unused heater outlets, helping maintain the correct airflow through the engine cooling system.

Fits:

• Porsche 911 1965-1968 2.0L / 912 SWB (F)
• Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
• Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
• Porsche 911 1978-1983 3.0L / SC
• Porsche 911 1984-1986 3.2L
• Porsche 911 1987-1989 3.2L G50
• Porsche 911 1975-1977 3.0L Turbo (930)
• Porsche 911 1978-1989 3.3L Turbo (930)

On air-cooled Porsche engines, the engine cooling fan supplies air to both the engine cooling system and the cabin heating system via heat exchangers. When the heating system has been removed, modified or is no longer required, the unused heater outlets must be properly sealed. These block off plates prevent valuable cooling air from escaping, ensuring it is directed through the engine's cooling fins where it is needed most.

Manufactured to OE Match standards, these plates provide factory-style fitment and are ideal for heater delete conversions, competition vehicles, engine rebuilds and concours-quality restorations.

What Do Heating Block Off Plates Do?

Heating block off plates are designed to seal the heater duct outlets on the engine fan housing or associated heating components when the original heater system is no longer in use.

Their primary functions include:

• Preventing cooling air from escaping unused heater outlets
• Maintaining correct airflow across the engine cylinders and heads
• Improving cooling efficiency
• Preventing dirt, dust and debris entering unused heater duct openings
• Providing a clean, factory-style appearance within the engine bay

Correctly sealing unused heater outlets is particularly important on air-cooled engines, where efficient airflow is critical to maintaining stable operating temperatures.

Why Do Heating Block Off Plates Need Replacing?

Original block off plates, or the components they replace, can become damaged, corroded or distorted after decades of exposure to engine heat, moisture and road debris.

In many cases, older vehicles that have undergone heater delete conversions may have improvised blanking plates made from unsuitable materials, or the outlets may simply have been left open altogether. This allows cooling air to escape, reducing the efficiency of the engine cooling system.

Replacement is also recommended if the original plates are:

• Corroded or rusted
• Bent or distorted
• Poorly fitting
• Missing altogether
• Damaged during previous engine work

Installing correctly manufactured OE Match block off plates restores the engine bay to a professional standard while ensuring the cooling system operates as intended.

When Should They Be Replaced?

Heating block off plates should be installed or replaced whenever:

• Performing a heater delete conversion
• Removing or modifying the original heating system
• Rebuilding the engine
• Restoring the engine bay
• Replacing damaged or corroded engine tinware
• Missing or incorrect blanking plates are discovered

Replacing worn or incorrect plates helps maximise cooling efficiency while improving the appearance and reliability of the engine compartment.

Porsche 911, 912 & 930 Heating & Engine Cooling Components

The air-cooled Porsche engine relies on carefully managed airflow to maintain safe operating temperatures. Every component of the cooling system, including engine tinware, ducting and heater outlet covers, plays an important role in directing cooling air exactly where Porsche intended.

When the heating system has been removed or modified, fitting correctly engineered block off plates helps prevent cooling air losses and ensures maximum airflow reaches the cylinders and cylinder heads.

Whether restoring a road car, preparing a competition vehicle or completing a detailed engine rebuild, replacing missing or damaged heating block off plates is a simple but important step towards maintaining engine efficiency and achieving a factory-quality finish.

Benefits of Replacing the Heating Block Off Plates

• Restores correct engine cooling airflow
• Prevents cooling air escaping through unused heater outlets
• Helps maintain stable engine operating temperatures
• Protects unused heater duct openings from dirt and debris
• Improves engine bay appearance
• Provides a factory-style finish
• Ideal for heater delete conversions and restoration projects