Prop RPM questions

[Blown Up]

I am currently running 30 pitch 3 blade cleavers on my Profile cat with twin 300's. I spin them right at 6200.
I am curious as to how 28 pitch 4 blade cleavers would run RPM wise compared to the 3 blade 30's.
What are the general differences is ride characteristics of a 3 blade vs. 4 blade?

[steve@scp]

adding a blade is usually like adding 1 deg. of pitch.
however that can be compensated by raising an engine 1/2" to 3/4"

4 blades like to run higher than 3 blades.

not sure of any formula that's exact. but that should get ya close.