I installed a Max prop on my 29' sailboat 3 years ago. I love it but I repowered this year and need to change the pitch and rotation. can you recommend a pitch. I was originally powered with a Volvo MD6A 10 hp. with a 1:1 ratio, I am now running a Yanmar 2QM15 with a 2.16:1 reduction. my prop is the 2 blade 13"