I need to correct that! I found another post on here I made last year and the figure was 5700 I think not 5200. Also forgot the rubber floor (pretty heavy stuff) at + 7.5kg.
I read a load of stuff on prop pitch and all the calcs to go through last night and Mercury's own prop calculator comes up with the same 9x9.
From what I understand I could go to a 10 pitch to increase top speed but that would lower pick up and bring me down to 5500.
Or maybe an 8 pitch to help pick up but that would lower top speed and raise RPM to 5900.
I want to raise top speed and pick up though which sadly I guess is unattainable in the same prop and the standard 9x9 is the compromise option?
I wonder if a stainless prop would offer any gains in this situation or going to a 4 blade which I gather lowers RPM by 100 or so due to the increased drag, although I guess SS props with thinner blades have less drag...?
I'll stick some links I found in below as they might be handy to anyone reading this topic in the future.
Choosing The Correct Propeller For Your Outboard | eBay
Understanding your Boat Propeller
Prop Basics, how propellers work
Understanding Propeller Pitch | Boating Magazine