I have a two blade Catto on a IO-360 7A with the nickle edges and have no issues in the rain, and I fly IFR too so that happens often. I am a little tail heavy, but I built the plane expecting that so it isn't too bad. A -7 would more likely need a heavy crush plate? It is a smooth prop with a 3000RPM limit, not that you would go that high. I do have to push 2600RPM if I want 165kts, and 2700RPM for 'full' speed, but that is so the climbing isn't overly compromised. Fixed pitch is definitely a compromise.
James Jula - CFI/II/MEI - N713JL RV-7A First Flight 10/12/15 - "What is chiefly needed is skill rather than machinery." Wilbur Wright, 1902
Last edited by jmjula : 03-17-2017 at 02:07 PM.