Re: Fuel Flow and Peak EGT


"Kobra" wrote:

While flying to FL from NJ last week I did what I always do and fly ROP by
75 to 100 degrees. This is how I was trained and my CFII is also my A&P /
IA.

I know enough about LOP to know I will not operate LOP without an engine
analyzer and probably GAMI injectors which I do not yet possess.

You are wise to err on the side of caution, but it is possible to run LOP
without fear of damaging the engine if you limit power. At 65% or below, it
can be done safely without an analyzer.

During the trip I was looking at my fuel computer and seeing an average FF
of 10.5 to 11.5 GPH at 6 to 7 thousand feet at about 22 to 23 inches MP and
2400 RPM at 75 degrees ROP.

What model engine? I often run LOP at those settings with a Lyc. O-360 F1A6.

I pulled my POH out and looked up the cruise performance numbers for those
parameters and those altitudes and I saw the recommended FF's. If I leaned
to the recommended FF's I was usually at peak EGT.

So my question is: Does Cessna advocate running at peak EGT in cruise? Or
if "advocate" is a strong word, are they at least saying "you can if you
want to" run at peak EGT in cruise? I've always heard that running at peak
EGT is bad for the top end of the engine.

Depends on the % power you're making.

--
Dan
C172RG at BFM


.

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