My EGT probes are more than three inches from the port so that might account for some of the difference between what I and others see and Lynn's experience. The hottest part of a flame is at the tip (like with a welding torch flame). Maybe the flame is longer than three inches coming out of the port? IDK.
Also, I’m still running lean or stoic. even on takeoff so that would account for some of the difference too. Only when I really really need max power do I richen the mixture. NA engines seem to tolerate this OK, turbos would be a different story. We are generally restricted to 6000 or less rpm on takeoff due to fixed pitch prop so That helps the engine live at higher egt. All things being equal, the car racers have a 50% higher heat load at 9000 rpm. They really need the fuel cooling of rich mixture.
Tracy Sent from my iPad
Lynn,
Interesting as the EGT can only be lowered by reducing power
-- or am I mistaken?? The engines seem to be able to run at 1800
EGT plus, so I no longer worry. Your thoughts??? Neil Unger.
Might I suggest 1600 as the highest EGT. 160
degrees for oil, 180 degrees for coolant and Best power.
About 12.5 to 1 fuel to air. Once at cruise leave at full
throttle and lean to lean of peak EGT and more to lean
stumble then richen to just smooth. All still at full
throttle. Low fuel burn, lower than peak EGT, longer
range and lower oil and coolant temps. All of this gets
better with a high power ignition. Mallory High Fire or
MSD.
Lynn E Hanover
In a message dated 7/29/2018 9:27:14 AM Eastern Standard Time,
flyrotary@lancaironline.net writes:
Thanks Tracy, so nothing out of ordinary
then. just did 1 circuit full at throttle. Will try
and take it higher next time & relax a bit. Need
to add a camera to record EM2 & efis as its all
just information overload at the moment. Everything
appeared fine on this post flight check, so thats a
first.
Need to go and re read all the manuals
again as its been such a long time since starting this
project. I very nearly lost interest but glad now that I
didn’t.
Andrew
Hi Andrew,
I regularly saw EGT temps at 1850 at full
throttle on take with a 13B. Were you at full
throttle the whole time? They should come down
at lower power. EGTs are a bit lower on the
Renesis. When boring holes at low throttle (17”
hg.) I see around 1525.
Finally managed to fly again this
afternoon, seems the new oil cooler has
done its magic now I found one that
actually lets the oil through (Mocal
34row). and is actually probably on the
cold side for oil & coolant, but I
can live with that for now. Can't give
accurate figures as it was a bit busy
around the airport, & EC2 has no
data recording function.
So now that I didn't have to fixate
one the oil temp gauge, I seemed to
gravitate to the next set of flashing
numbers, EGT at 1875 seemed a bit high,
adding fuel just made it run rough, did
try leaning to the point of rpm drop,
A/F went above 18:1 but EGTemps remained
when I expected a drop due to the lower
power. so not sure whats going on, maybe
EGT probes are too close to engine at
55mm from the ports and are still in the
flame.
Would appreciate input from the
group, otherwise I'm likely to cut the
egt wires and fly in an ignorant bliss.
--
Regards Andrew
Martin Martin Ag
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