This is a continued discussion from a thread on lightweight rocker arms:
http://forums.pelicanparts.com/newreply.php?do=newreply&p=5119566
Quote:
Originally Posted by Steve@Rennsport
Hi Sherwood,
Walt is right,...it takes about 30HP+ to drive the Porsche flat-fan. This was well worth it on our 935's, but having 600-800+ HP, it was not an issue. The big reductions were cylinder head temps which established how much HP we could make,.... 
My apologies for the digression. |
Hey Steve,
Can we extrapolate the following?
If:
30+ HP for 600-800HP
then:
X HP for 200-300
Would it be 1/3 to 1/2 (10-15 hp)?
What's the loss from the existing vert. fan, belt drive?
Is a gear drive the optimal drive system? Is there an optimal fan configuration for all engine speeds?
For starters, here's a Wiki article on propellers (e.g. fan blades) that contains some interesting facts.
Sherwood