RE: 3 blade or 4 blade prop for TF p-51
I have been told in the past that if you go from a two blade to a three blade you either go down one size or go down one pitch. Pick your poison. I cannot say that this is a fact but it has worked for me. So if you are using a 14 x 8 two blade then you would either want a 14 x 7 or 13 x 8 three blade, if they are available. Like I said that is the method I was told and have used. There are alot of opinions on this so you will probably have to trail and error it. I cannot comment on the four blade because I have never had the desire to try one.