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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.