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Hello all, I've owned an '86 252 for coming up on two years now that I continue to learn about. I'm learning about LOP ops. I've researched many articles and also many posts here and elsewhere regarding this topic. I'm curious what kind of peak EGT spreads (a.k.a. "GAMI spread"; not peak EGT value difference) folks are getting (or got) out of their stock TSIO-360-MBs or SBs. A question that I can't find an answer to is: How much roughness on the lean side is too much? I don't want to start a ROP/LOP argument, but hopefully we can all agree that with a fixed MP/RPM power generated decreases quickly as we continue to lean past peak, which can cause power imbalances and roughness when all cylinders are not operating at the same mixture. A lot of LOP ops articles will say that you cannot run LOP if it is rough, but how do you determine that? I have a spread of ~0.5 gph at a MP the book calls 65% (it's not actually 65% of course unless the mixture is at the book-specified ratio). I can go about 30 LOP and I wouldn't call it "rough", but it is perceptibly different. I can't feel any new shaking feeling in the pedals or the yoke. The whisky compass seems to shake just as badly as it does any other time. BTW, the prop seems well balanced on this aircraft. During one flight, while operating very LOP, my wife--who doesn't get into the details of my neurotic FE-like fiddling, only recognizes that I am doing "something"--asked "why is it running so rough?" I'm assuming that's too much! But I was about 80-100 LOP at that point. I, personally, believe in trying to run LOP (I'm fine with it if you don't) but I definitely don't want to crack anything by doing it. Thanks for your thoughts!