The fresh air that flows inside comes from the nose grills, and then is blown into the vehicle through a tube on the inner wing.
The air duct is welded against the inner wing or exposed to water splashes from the wheels, you can imagine that there are many Karmann Ghia's where these ducts are so affected that they have rust holes.
The tubes, which are present on the left and on the right, consist of two parts; a front part that connects to the ventilation grill housing and a rear part that was not available separately at the factory, for this it was necessary to buy a complete inner wing.
The complete inner wings are no longer available, but the rear part of the air duct is now available separately, together with the front part you can replace the complete air duct.
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