I have run an os 91 in my BVM fan for about 30 flights before it smoked the piston. I know the OS would like to run at a lower RPM. Is there a different fan that can be run on the BVM Viojet that will absorb some additional HP for longer engine life?

Will the Viofan (96 version) fan work and /or is it pitched to throw more air?

Thanks for your response.

Paul