Originally Posted by MountainU2
I shoot for <= 380 CHT, and my usual flying is at 6500 or 7500ft in the SF Bay area. I find my MP at cruise and full throttle is 22-2300, and I set the prop at 2300. Then I lean until peak, keep going until slightly rough, then back in a couple turns. I end up with about a 1250 EGT. Seems like about 130-140 kts IAS is where she’s happy.
Mountain, I just got an RV7A and am also switching from 10 years of fixed pitch prop. There's a fellow named Deakin that is real good explaining this. There's a youtube with a guy quoting his graphs that I saw last night, but can't find now.
In that video using Deakin theory, they have a "red box" described as Peak EGT to 100* ROP, as this is the area where the engine is under the most stress *IF* producing 75* power (only at sea level). They recommend 25* LOP or 100* ROP and to try avoiding operating in the "red box". The red box isn't necessarily bad, but can reduce engine life if you're in it all the time (as I imagine a lot of rentals probably are).
In my previous Tiger, leaning your method was EXACTLY the same as attempting to do all of the above, but I was usually at 15* LOP. A lot of carbed engines can't handle lean of peak as fuel flow varies per cylinder if not injected.