<VV> Fans/.my take

[levair at aol.com]

Of course the Corvair fan is inefficient for a fan.
It is not a fan; it's a centrifugal (centripital?) blower.
It is akin to a Paxton of Vortech supercharger or a turbocharger compressor.
The top shroud is the compressor scroll. Just like a supercharger, the scroll needs to be a tight clearance to the compressor blades. The Corvair scroll directs/flings the compressed air (2 to 6 psi) right out to the cylinder heads where the cooling occurs. The cylinders are primarily oil cooled --preferably by a huge remote front mounted cooler.
?? As a compressor, it is extremely efficient (much more than a fan) in a sweet spot just like any other centrifugall compressor and inefficent below that spot and goes into surge/cavitation above that spot . The cut down racing fans are trying to avoid that cavitation.
?? Porsches have?FANS? that are linerally inefficient. Corvair compressors are non linerally efficient.
?? The pulley changes are to move that "sweet spot" to the rpms being used i.e.; 4000 rpm for street sweet spot and change the pulley ratios (slower) to move the efficient sweet spot to the racing 7000 racing rpm.
?? Changing the straight blades to curved ones?improves the efficiency and is available as a "hop up" for the Paxton blower.
?? The case cover/fan mount is streamlined properly.

All and all a very good job by GM's aerospace engineers.

Fire away,
Warren

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