Originally Posted by hickswm
I installed 6 cylinder pmag in my rv10 in March. I installed with std settings. Fixed 25 deg. Btdc and advanced up to +9 deg or 34 deg btdc in variable position. On hot days I have to leave in fixed position and reduce power shortly after takeoff to keep cht below 400 degrees and also keep higher fuel flow. In cruise when I change to variable I see higher egt and slightly higher cht at same fuel flow before I replaced the magneto. LOP 12-12.3 gph. Starting hot or cold works well but I had a slick start and it started well with that. The jury is still out for me on pmag at almost twice cost of slick mag.
Please read your engine operating handbook. Lycoming states 435 degrees is the max for continuous operation and 500 as the upper limit. It is not unusual to see climb temps over 400. The goal is to get them below 400 in cruise, not climb.
Originally Posted by Lycoming O & IO-540 Oper Manual
See Page 3-5
Never exceed the maximum red line cylinder head temperature limit. [Max Cylinder Head Temp is 500°F (260°C).
For maximum service life, cylinder head temperatures should be maintained below 435°F (224°C) during high performance cruise operation and below 400°F (205°C) for economy cruise powers.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC
Last edited by N941WR : 05-19-2020 at 08:11 AM.