Your performance will vary depending on the conditions and fuel used, , with an 11X5 you should get over 12,500 rpm on the top . Idol should be around 2500 or whatever it takes to get your airplane on the ground, depending on the airplane the lower the pitch the higher you idol can be and still land, I had a 76" J3 cub that was extremly hard to get on the ground with an 6 or 8 pitch prop no matter how slow the idol. Obviously there are limits to how slow it will run reliably . No matter what you will probibly need to burn a dozen or more tanks of fuel before it will be at its best.