The fan with the 11 blade rotor is a Dynamax by Tom Cook at JMP. The pitot pressure works very well to pressurize the fuel system. Looks like you have JMP System II tuned pipes also. You can't do any better than what you have unless you go turbine. IMHO you won't pick up any performance by going BVM unless maybe you go with his latest fans and BVM .96s and if you're going to spend that much money, you might as well turbinize her. Dynamax fans have been flown in larger and heavier airframes than anything BVM powered.