"TripFarmer" wrote:
I've got about 15 hours on 6 new Superior Millinieums and just
put in my first quart of oil since 2TT. I have a range of temps
at cruise from 320 - 380. They dropped a lot after about the
first 30 - 60 minutes of break in and seem to have stabilized
since to these numbers. The hot one will run 400-410 in a
full power climb in my PA28 235.

I have the same cylinders in a LYC O-360; they have 500+ hours on them. In
order to keep mine below 380 deg., I have to keep the cowl flaps wide open
in cruise in summer at 75% power. I can lean the engine in climb for better
performance, but it takes careful attention to the mixture to keep the CHTs
under 400.
--
Dan
C-172RG at BFM