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Alright Mooney group bear with me, this may get a little long winded. New Pilot and even Newer Mooney pilot. So, i just finished my 15 hours to be checked off by insurance. I now have about 20 hours in my new (to us) 1967 F model. We bought it with about 25 hours on a new engine, and just completed our first oil change as well. Lots of firsts going on here. So, I am new to complex aircraft as well. When performing our run up we normally lean the mixture to best power similar to what we did in the 172. Run up to 1800 rpm, full forward on the prop, and slowly lean until power loss catch it and give a few extra turns once the power is back. Then we pretty much haven't touched the mixture on any flight. I played with it a little the other day in cruise, lowering it until it got rough and then adding it back in until it was smooth. Our checkmate checklist says cruise around 2600 rpm on the prop, but once setting the prop you cannot use RPM as a good lean indicator correct? Plus to add to complication our fuel pressure gauge is out (so I cant just put it at the bottom of the green) which would be running it efficiently correct? (Also new avionics coming in a couple months) So the only time I have tried to lean it in flight was in a cruise the other day I leaned it until it ran rough, then twisted it back in to run smoothly. Which the POH says don't lean the power above 75% power... but at full throttle I am sure I am above that. Did I hurt the motor? How on earth do you calculate percentage of power? Then there is the throttle. I figured on a brand new engine you wouldn't want to run it at WOT all the time due to wear on a new engine. But my CFI said run it full and manage RPM and Fuel flow with the mixture and prop, but my Dad (Airforce Pilot/commercial pilot of 30 years) said he would also be worried about wear on the engine, but thoroughly admitted I probably have more experience in a civilian airplane than him at this point. Ours is also turbo normalized as well, and all I have been told about it is to keep it below 28 MP. All of this has added a ton of confusion in my mind, so I went to the internet. Specifically another post on here: Which added even more confusion. I also realize I probably sound like an idiot, but I am okay with that if it helps me figure all this out by asking the experts. So to summarize my questions: 1) Is our best mixture practice during run up correct? 2) When leaning for efficiency, can you use RPM drop with a constant speed prop, fuel pressure indication, or leaning it until its rough then adding it back in? Which is correct or are all correct and some are just better than the other. 3) Is WOT the correct way to fly? Is the POH out of date as stated in the message board above. 4) Is 2600 RPM that the checkmate suggests the best cruise setting on prop? 5) Have I hurt the engine buy leaning with full throttle in and potentially getting over 75% power setting? 6) How on earth do you correctly measure % of power? (This one is probably easy but I am missing it) 7) Does any of this change when adding in the turbo? Thanks everyone!!! I know that is a lot to follow but any response, guidance, or videos would be much appreciated. Fly safe, The FNG

Based on the related thread in "Modern Mooneys," I've been considering this topic but didn't want to muck up commentary on someone's big bore Continental with balanced injectors by blabbing on about my trusty but primitive carb'd Lycoming O-360. Specifically I've been musing about my EGTs and leaning technique in climbs to high DA,, or takeoffs from high DA. Though I've never actually done the latter, I might make it to Leadville one day. Because leaning to "target EGT" at WOT seems precarious to me, I decided to figure out as accurately as possible what that target value is. I looked at my JPI data from 50 flights, all of which were from near sea level and done in the colder half of the year- starting in Sept 2015 when the monitor got put in, until March this year. There was minimal variation except that two clear patterns emerged - in 70% of takeoffs, EGT on #4 was the hottest, with #3 100 degrees cooler. In the remaining 30%, #3 was the hottest, in which case #4 ran 100 degrees cooler. Peak FF was always in the 17-18gph range. Means and std. dev. for peak EGT on takeoff are shown below for the 2 patterns: Cylinder: Pattern 1 (#4 hottest): Pattern 2 (#3 hottest): 1 1260 +/- 11 1280 +/- 9 2 1296 +/- 14 1253 +/- 13 3 1321 +/- 20 1431 +/- 23 4 1427 +/- 18 1326 +/- 13 CHTs also run hotter in 3 vs 4 depending on which has the higher EGT for a given takeoff, making me think the two patterns reflect real shifts in mixture distribution, not measurement artifacts. There is no rhyme or reason to which pattern appears- it can shift on consecutive takeoffs under identical conditions on the same day. FWIW, I suspect neither #3 nor #4 is actually the leanest - #2 EGT usually but not always peaks first on leaning in cruise, and its CHT usually runs second hottest in climb (despite lower EGT), irrespective of whether 3 or 4 runs hottest (both CHT and EGT). Anyway, my only takeaway so far is that I can safely lean my hottest EGT (#3 or #4) up into the low 1400's to optimize power and improve fuel efficiency on a long climb, as long as the CHTs tolerate it. It's interesting to note that with a single probe EGT, this might have been a bad idea given the two distinct patterns of mixture distribution. Reasonable? Any other points to consider? Also, regarding high DA takeoff rolls (I have no experience), accurately tweaking the mixture to get low 1400s EGT seems precarious as heck . I have enough trouble staying on the center line, watching the ASI, checking the essential gauges, thinking about abort point, etc. in unison. It might be feasible if I used a particular high altitude field on a regular basis so could learn to set it roughly by instinct. The more complex technique to lean for high altitude takeoff has previously been covered well here.