The following is an excerpt from a Mike Wills post several months ago:

“Anyone trying to tune up Tracy's EC2 without either having an EM2/3 or Ed Anderson's EFISM, you're wasting your time. I spent the better part of a year tweaking the MAP table and thought I had it pretty well done. On my first flight I spent a fair amount of time fiddling with mixtures and had a couple of rough running spots. I installed Ed's EFISM and spent 2 days tweaking. In the process I got the engine running smoother than it ever has and now have it is idling nicely at 1350 RPM. That’s 300 RPM lower than I was ever able to get it previously. In my opinion you really HAVE to have some sort of indication of what is loaded in the MAP table to effectively tune it.”

I whole-heartedly agree!! I installed ED’s EFISM last night and was anxious to see my MCT – let’s just say it was a mess. There were a few points, mostly around the staging area, where I could see that some tuning had taken place; however, there were several locations with wild swings from one bin to the next. These wild variations appeared in the middle of the high rpm band where the engine has spent very little time, as I’m usually near idle or WOT – but man it sure is nice to actually see what’s going on.

Jeff