you guys are way overproping your engines
a .46 will never turn a 11x10, 12x6 at any reasonable rpm. try a 9x8-9 (speed) 10x7-8 (fast sports flying) , 11x5-6 (sports flying), 12x4 12.25x3.75 (3d)
a few things are wrong with the above
a larger dia prop with a low pitch (12x4) DOES grab more air than a 10x7 for example, but it wont move the air it grabbed as fast this gives you lower stall speeds and more vertical.
a 10x7 would give you more speed, less vertical and a higher stall speed
what does all that mean, well it really depends on what the plane was designed to do. most sports planes like a 11x5 or 10x7 with a .46 sized engine.
what plane are you going to use? if its a trianer i recommend a apc 11x5, its plenty fast at full throttle but will slow the plane down at idle.