Paul,
Looks to me that you have a spread of about 0.4 which - as far as I understand - is pretty good.
Suggest you send it to GAMI. They will look at it and give you a better educated opinion. They will NOT recommend you get their injectors if you don’t need them. ( I sent in a lean test on my Mooney Ovation and they told me it was fine as is)
D. Brunner N241DB 700 hours
GAMI injectors
From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of Paul Miller
Sent: Sunday, November 03, 2013 4:48 PM
To: lml@lancaironline.net
Subject: [LML] GAMI lean test IO550N
I haven't run a lean test on this IO550N before. I've never removed the injectors in 768 hours.
On my way from Calgary to central Florida (one stop in Omaha, never done that before) I ran the lean test with the following basic results. I'm interested in any feedback from this graph. I ran this test at 9500 feet and by the end the test was getting about 230TAS and all CHTs below 300 LOP. I had good tailwinds so I was grounding 270K and flew Calgary to Omaha on 51G of avgas at 13,500. As usual, I did that entire trip VFR with great help all the way from controllers.
PS: Over the Atlanta arrival route I was asked to remain at 13,500 until clear. I encountered the top of a misty mountain for about 15 seconds. The windshield had some light crystals which disappeared immediately. The wing leading edge had 1/16 inch of very light rime (I could see the line down through the landing light cover) like a white pencil lead laying spanwise along the leading edge. You could barely see it. I'm sure the prop had something similar. I lost 20-25 knots in a heartbeat and never got it back for half an hour. It was -6C.