Remixed the design to improve the venturi as well as to create a mounting ring to connect it to the fan housing. The motor opening is sized fits 27.5mm high RPM DC motor (Warning! Wear safety glasses when running!). You can modify it in thingiverseTinkerCad (link: https://tinkercad.com/things/4qNDr1YfoAO) for different size motors.
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Just About any 200mmx200mm
Would print the impeller at 50% with double shells, the housing can be around 25% infill while the top and ring can be 5 to 10%. Also you might want to scale down the impeller to either 95 or even 90% depending on the fit your looking for (becuase of file size the impeller is not in the TinkerCad model.