Heavy Planes
When you are converting to a three blade prop, you reduce the diameter by one inch. A 46 that uses a 11- 6 two blade, will use a 10-6 three blade.
The choices af props in the three blade variety is rather limited. They are generally only available in the 6" pitch range.
The evolution 3 blade from Horizon has a low pitch and is for a 46 size engine.