In our -9A we have the following engine and details
IO-360-180hp Superior EX built by Penn Yan,
Vertical Fuel injection
Roller tappets
2 Slick Mags with dual impulse
100hrs total time.
When we first installed the brand new engine, we moved the timing ahead about 1.5' to be about 26.5 BTC, rather than 25' BTC. Penn Yan ran the engine for about 45 minutes on their test cell. Oil consumption was excellent when I first operated it.
Our reasoning being for advancing the timing;
: I've always felt that 25' was an arbitary, conservative number,
: the plane is light, so are the loads
: Once the wheels are off the ground, we pull power back to 25 square.
: Electronic ignitions in cruise operate close to 40' BTC as I understand.
After 100 hours of operation, while doing the Condition Inspection we found the following.
All cylinders are 78/80
Oil consumption is approx 1 quart per 15 hours (Aeroshell 80) (Aeroshell 100)
Cruising at 23 square we are burning 8 gallon/hour. Might even do better when the injector in #1 cylinder is enlarged to reduce EGT in this cylinder. It's about 35-40 degrees hotter than the other cylinders, so have to lean to this cylinder.
Has anyone else with standard mags advanced their timing slightly?
Jack
IO-360-180hp Superior EX built by Penn Yan,
Vertical Fuel injection
Roller tappets
2 Slick Mags with dual impulse
100hrs total time.
When we first installed the brand new engine, we moved the timing ahead about 1.5' to be about 26.5 BTC, rather than 25' BTC. Penn Yan ran the engine for about 45 minutes on their test cell. Oil consumption was excellent when I first operated it.
Our reasoning being for advancing the timing;
: I've always felt that 25' was an arbitary, conservative number,
: the plane is light, so are the loads
: Once the wheels are off the ground, we pull power back to 25 square.
: Electronic ignitions in cruise operate close to 40' BTC as I understand.
After 100 hours of operation, while doing the Condition Inspection we found the following.
All cylinders are 78/80
Oil consumption is approx 1 quart per 15 hours (Aeroshell 80) (Aeroshell 100)
Cruising at 23 square we are burning 8 gallon/hour. Might even do better when the injector in #1 cylinder is enlarged to reduce EGT in this cylinder. It's about 35-40 degrees hotter than the other cylinders, so have to lean to this cylinder.
Has anyone else with standard mags advanced their timing slightly?
Jack