The duct has a very steep angle but since it is totally enclosed flow separation isn’t an issue. You can see how the duct lines up with the rear keel so the duct won’t interfere much with the diffuser effectiveness we think.
One of PZ’s very unique rear aero features is the internal diffuser passage. You can see its exit right above the license plate recess in the trunk. To our knowledge, only PZ’s car and the Nemo Evo have used this feature with success.
The outlet of the internal diffuser has these flow straightening dividers on its exit. The duct itself has a diverging shape internally.
Here is an internal view of the duct. We were very fortunate that William was very open and transparent about his aero and let us have clear access to photograph everything.
The rear wing is an APR1000 unit with a swan neck mount. Swan neck mounts interfere with the critical underwing airflow less than conventional mounts and are thus slightly more efficient.
PZ Tuning made these superlight carbon fiber doors out of vacuum bagged prepreg. We think that the aero and body panels are where most of the money is spent on this car.
The leading edge of the door, the rear wheel wells, and the side skirts are all designed to enhance the exit of air from the wheel wells, recover pressure from the swirling air around the front tires and thus increase the effectiveness of the front wing and splitter.