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temps
Skymaster
The TIT has never been a concern. Running 1450 up to 1525 depending on power etc. Never had them close to 1600 as I only lean DURING CRUISE or DECENT, otherwise mixture is to the wall.
If you are running 65% power or less then I do not see how you can burn valves. You must have been running higher power.
Do you have intercoolers?
The TIT will drop when going LOP. If running LOP (heaven forbid) you need to insure your last cylinder (to peak) is 50-75 LOP otherwise you can/could burn valves but more likely 0-40 ROP. I am more concerned with EGT's that TIT. In the 337 the TIT is more likely to be the EGT of the last cylinder UNLESS you are wasting fuel and the unburned fuel is igniting in the exhaust stack (burning)... then the tit will be higher.
Some people will use the PEAK on the JPI/Gem to determine peak but there are *5* more cylinders to LEAN before you are LOP.
The other good test is to roll back mixture until the engine starts to "baulk"... richen till smooth... then look at your fuel flow. Then slowly richen and monitor EGT. All cyl should go UP then start to FALL OFF. If one starts to fall off then that cylinder never did reach "peak" and it is still on the ROP side. Depends on how close the cylinders and injectors are matched.
You are more likely to burn valves running lean at higher power settings especially in the climb. Always important to monitor full rich / full power fuel flows to make sure they are in spec.... rest should track.
How do you calc your power if you have intercoolers? Is the tachometer been calibrated recently? and--- what is the fuel flow at 65% power?
I always have found CYL2 running hotter than the rest. I have found the TITs closely matched when the engines are running same fuel flow during cruise to within 5 degrees.
There was a baffling change on the engines around s/n 225 and higher (around '75 or later and the temps improved somewhat.
bob
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