Novel FI Tuning Idea, I'm sure it's been done.... Options

[McMark]

I was thinking about graphs (see my Excel help thread) and I go to thinking about how to use this datalog information to help me see where my FI map is wrong. It dawned on me that the two major input for this KitCarlson system are TPS and MAPS. The result or output would be RPM. So if you graphed TPS on the X-axis, MAPS on the Y-axis, and RPM on the Z-axis you should be able to see where you've got problems. Of course you would have to average your readings over time since you would have a lot of repeat data in the cruising RPM range. What are your thoughts/responses to this idea?

[DNHunt]

Mark

Is it possible to log O2 readings also? To get a rough map I use the FI in closed loop with a really large correction and look at the MAP and RPM points where its really working to correct. I then change those points. Finer tuning I use a viewer like you are talking about. The graph makes it easy to see where to change. My only problem has been avoiding the temptation to use readings that lie between the RPM and MAP specified values. Also, O2 values are different at the same RPM and MAP points depoending on whether the engine is under load or compression. I tend to ignore the p[oints that are under compression.

Jake

I have found that my injection goes way lean >18 on decel when it's pulling high vacuum. I've ignored that cause I really don't think I can do anything about it without something like a decel valve. I then set the acceleration enrichment to give a small squirt as soon as the throttle cracks. it seems to work. Incidentally, I should be starting on my rebuild soon. I wanted to use the old engine as a test mule for the FI and ignition so i won't repeat my problems.

Dave