Manufacturer HP numbers are the biggest scam in nitro. A typical high end .28 engine may be making a legitimate dyno proven 1.6 HP, nothing like what the manufacturer says. So that 45,000 RPM (which at that high of RPM there is no usable power, and in a boat, good luck getting a nitro engine spooled up that high unless its got cavitation issues) is just some bogus number they throw out there, as is that 2.75HP number, don't believe it, don't bother quoting manufacturer HP numbers.
Also, to my knowledge ceramic coatings are not meant to be applied in wear applications like a piston. It will not make it any stronger, and being a coating, it will be very difficult to have it applied 100% evenly, which in our tiny RC 2 stroke engines, its important that the piston/sleeve have as even of a surface as possible in relation to each other.
Quite a few engines out there have TiNi coated cranks, this is old news,
nothing new. But it really only helps at the crank pin for wear resistance, other than that there is no point to it really, if it's done to promote smoother flow of fuel/air through the crank, the same thing can be achieve via polishing.
You can run 40% nitro on a Picco .28, you just have to shim the head accordingly. And honestly, WTF are you doing that requires 40% nitro with a .28? If this is for a drag racing application you are going to be much better off with a high end .21 onroad race engine meant for high RPM and running 30%.
Just like HP, newbies think nitro content is the magic number and they think the more the better, which just simply is not the case.
To me this just seems like a stupid idea to want to have custom coated/plated stuff in an engine, there are more than enough engines out there that will fit your application, cost you less vs. a cheaper engine and getting parts coated with w/e it is you want, be more reliable, less headache with tuning, run better overall, etc. etc., and will do all of that much better than any engine with a "ceramic coated piston" and "ceramic coated exhaust header" and "70% nitro". You have to remember that there is a very big (obviously) difference between what works in the 1:1 world and what works in the RC world.