Now that I have the 340 Buick running under '411 control, it's time to make it run well. A bit more complicated than adapting a Camaro tune, redline is set to 7500rpm and MAP to 170. All the usual, fan controls and such are done. The car is fitted with a wideband and EGT gage but neither of those are connected to the controller. The injector flow is set to 4.4gm/sec for 35lb injectors. I have run my first datalog using OBDwiz but am not impressed with the available choices for PIDs. I have run datalogs before on MS/TunerStudio and am comfortable with that type of graph display. Can anyone suggest better datalogging software?
As it stands right now, after starting the engine leans out badly and wants to die (14-15:1) and then eventually goes very rich and settles down to a nice idle (11:1). My datalog may indicate it is still in open loop, or I may not have the right PID included. Is this determined by engine temp, O2 sensor temp, or a time constant?
For initial set-up I've made use of the squirt bottle technique to verify rich or lean conditions and adjusted prime pulse and cold enrichment (B3632) as well as wholesale adjustment of the main VE table and the OL table (B3605)
First off, it seems counterintuitive that if it runs rich in OL after all the enrichments have timed out, that the enrichments could have caused any sort of a lean condition. Something else must be going on here but I don't know what. This, I think is the most important issue for getting on with the tuning.
What I'm missing here is a thorough understanding of which enrichments do what and how to tune them. For instance, I can easily accept that I may be missing a critical table, or that I'm adjusting the wrong thing. The B3632 table for instance. If it decays based on B3650 then how can it suitably compensate for coolant temp? And if it doesn't then why does my mixture go lean soon after starting? I richened it up quite a bit.
If anyone would care to have a look at this, my Bin and datalog are on the laptop but I can attach them. I just have to post this first then move over there.
Jim
Got the bin attached but it said the log was invalid. Not sure what to do about that, it was only 15kb.
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