185 Lean of Peak on Floats

[bona]

My $0.02 fuel is cheaper than cylinders,

I've always run rich of peak. more gas running through will keep it cooler, lessening the risk of burning a valve or head etc.

[klmarsha]

I have run my 185 in commercial operation lean of peak since I put GAMI's and an EDM engine analyzer in. My mechanic is a 185 guru and was the one to suggest it. He has many customers that have flown right to tbo without issue while running lean of peak. As several posts suggest, it does require technique and an engine analyzer. You MUST be able to monitor each cylinder because if you do have one going south (cracks around exhaust valves are a -520 curse), you will cook it. I was able to see fuel flows as low as 11.8. Its actually pretty amazing with the GAMI's (provided you do the matrix and change injectors until temps are exactly even), you can lean until it doesn't have enough fuel to stay running and temps stay down. Pratt and Whitney did a study about proper leaning just after the War, and they discovered that lean of peak is actually the coolest place for most recips. I'll look for the study and post it here if I find it. My 2 cents.