That depends on how precise you need it to be. The irregularity of the shape makes it impossible to do an accurate calculation based on single formulas. So it then becomes a matter of how much of an error margin is acceptable.
Best regards,
Leo van Miert
Horsepower is how hard you hit the wall --Torque is how far you take the wall with you
Leo van Miert
Horsepower is how hard you hit the wall --Torque is how far you take the wall with you