Learning a Turbo

This stuff isn't rocket science. Throw however much fuel at it is required to maintain a max cylinder temperature of 380 and to remain below whatever your turbo's TIT limit is. If you are full throttle, that'll require full mixture, and in some continentals a fun abuse of the high boost pump to slam even more fuel in. If you are less than full throttle, you can likely lean things out a bit, using the previously mentioned limitations to help you judge how much.

If your max CHT temp and turbo temps are happy - you aren't hurting a thing. If you don't have instrumentation that lets you see the TIT and individual cylinder temperatures, buy that instrumentation. Nobody can afford to run a turbo airplane without it.

I typically do a very rich of peak climb followed by a very lean of peak cruise. Once you know the "right spot" you can quickly set the mixture to where it needs to be for LoP then fine tune a bit to get it right. Unless you're at minimal power settings (like below 65%), it is best to not spend much of any time between "very rich" and "lop", well, unless you like big maintenance bills.
 
jbehler said:
Agree completely....frequent utilization trumps manner of utilization in all but the most extreme examples. With utilization as a constant, I would guess the longevity sweet spot for a properly equipped big bore engine would be 65-70%-ish power and LOP. Of course in some planes that results in a major performance degradation vs. book max performance and it's up to you as an owner or pilot how much you value extra performance when weighed against the potential of shorter engine life.
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I'd open it up to 65-75% if reasonably cool. Personally have run 3 large bore turbo'd engines (1 TIO540-AK1A as in this thread, and 2 TSIO520s) well past TBO running ROP with no issues (i.e., no cylinders ever pulled). But, all three engines in two planes flew around 200 hours per year. LOP may save fuel, but at least in my hands, ROP has had no detrimental effect on longevity of the powerplant.
 
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