My engine has been setup to 30 gph
at full power. Perhaps the difference between your 1300 and my 1100 is the
difference between 8.5:1 and 10:1.
I’ll check to see what my
hottest EGT is on takeoff.
Doug
From: Lancair Mailing
List [mailto:lml@lancaironline.net] On Behalf Of Steve Colwell
Sent: Tuesday, July 13, 2010 5:51 AM
To: lml@lancaironline.net
Subject: [LML] Fuel Control problem
On another point – you say you
lean to 1300 degrees on climb out. I am surprised by 1300 degrees.
(Although I know that EGTs can differ according to installation, and since I
have a 10:1 compression engine my EGTs should be lower.)
I arrived at 1300 degrees
as recommended at the Advanced Pilot Seminar after Sun n Fun last year.
Assuming you have a fuel flow of at least 29 gallons per hour (they say 30 is
better) on a stock IO550-N, look for the hottest EGT on the hottest cylinder
(mine is #6) during takeoff to about 150’ agl on a near sea level runway.
They say this is a safe number to continue to lean to during the climb.
How much ROP are you when you
climb?
I’ll have to check.
Steve Colwell
Legacy almost stock IO550-N with stock pistons
From: Lancair Mailing
List [mailto:lml@lancaironline.net] On Behalf Of Douglas Brunner
Sent: Monday, July 12, 2010 2:53 PM
To: lml@lancaironline.net
Subject: [LML] Re: Fuel Control problem
Steve,
I always put on low boost above
10,000 for “vapor suppression”. On several occasions, I have experienced
fluctuating decreases in RPM that I attributed to “vapor in the lines”.
Putting on the low boost seemed to solve the problem.
From what I remember of the
Advanced Pilots Course (I took it in Jan of ’06), they suggested that the
problem occurs with hot fuel at high altitudes – and your story seems to
be just that. Suggest you try using low boost over 10,000.
On another point – you say you
lean to 1300 degrees on climb out. I am surprised by 1300 degrees.
(Although I know that EGTs can differ according to installation, and since I
have a 10:1 compression engine my EGTs should be lower.) I lean to
1100 in the climb until I reach 70% power at which time I lean to 1200.
Since my peak EGTs are around 1325 (when I lean at 70% - probably higher at
higher power settings), I figure I am at least 250 ROP when above 70% in the
climb.
If you lean to 1300 in the
climb, what do you think your peak EGTs are?
How much ROP are you when you
climb?
If there are any “lurkers” from
APS, what do you think of 1300?