I used to see temperatures like this in my IV-P (TSIO-550). The problem
turned out to be incorrect setup of mixture and fuel flow at idle and full
power.

It turned out to be impossible to set the full power fuel flow on the
ground. The brakes could not hold the plane and it just felt unsafe. When
the shop set up the engine the approximated the full power settings because
they did not dare to run it at full power. Perhaps this is why others have
incorrect setup as well.

By doing several flight tests we set the full power fuel flow to the book
number (42 gph instead of the 38 gph I had before) and did the same for the
other fuel flows. This changes the mixture profile at intermediate throttle
settings.

Now I climb out at 310 to 360 on a hot day. I cruise lean of peak at about
16gph 2400 and 27 inches has temperatures in 300 to 310 range.

One word of caution: use a long runway. When you set the fuel flow too high
and use full throttle you will start your takeoff and then the engine will
die from being too rich. Not a happy program if you don't have enough runway
to land straight ahead.


-----Original Message-----
From: gerardoconnell@optusnet.com.au [mailto:gerardoconnell@optusnet.com.au]

Sent: Tuesday, June 03, 2008 7:46 AM
To: lml@lancaironline.net
Subject: CHT's-Lycoming 0-320 (LNC2)

Since installing an EDM 700 I notice my cylinders running around the 380 to
415 deg C

Number 1       380 deg C
Number 2       380-398 deg C

Number 3       380-395 deg C
Number 4       415 deg C

Number 4 reaches 430-450 in the climb out at 130 KIAS

I am thinking of putting 2 NACA ducts in the top cowl to address
particularly NO 3 & 4 temps

What say ya'll

Gerard