Catto 3 blade with injected (upgraded) O360-A4M.
2500 RPM = 155 KTAS @ 7.8 GPH
2550 RPM = 160 KTAS @ 8.1 GPH
2600 RPM = 165 KTAS @ 8.5 GPH
Planning an upgrade to the Superior cold air sump, which is stated to add 7 HP. I'd love to get 175 KTAS.
Thanks Ray, is the Catto smooth and reasonably quiet at 2600?
Bob Bisbee
I do the same burn for the same speeds with my 7. 175 is available, but with higher burn rate. All at 2450 RPM, CS Hartzell. Typically, 160KTAS @8.0-8.1 GPH is the cruise setting, speed will go up/down with mixture to above settings. All around 8000 ft DA, it is better for mine at 10K. 180 HP M1B.
I have an 0360 A1A (carb), and a 3 blade catto on the 7A. Routinely I cruise at about 55% power (around 2300 RMP or so) at 134 kt. on a trip from VA to SC. Fuel burn is just under 7 gph depending on altitude and leaning....most altitude is at 6,500 ft or less.
3 blade Catto Prop is smooth as butter.
Paul