Quote:
Originally Posted by Jordo!
Also, regarding fuel trims, note that there are most likely multiple trims --one associated with each cell in the fueling map (which you probably can't access) or at least a block of adjacent cells; cells are graphed by load (based on MAF value and known engine displacement) and RPM.
Short term trims (based on vacilations around 14.68 AFR / narrow band .5 volts) are averaged to create long term trims. One of those is probably carried into open loop (can Modshack confirm or refute that?)
The LTFT of +34 may or may not be a cause for concern. So long as driveability is fine, AFR's in WOT are fine, and the CEL light is off, it's not ideal, but acceptable (ideally, you'd want to have th ecar tuned so that these are all in the single digits and driveability is excellent).
Man, I can't wait to start playing with uprev on this car  |
I don't know how sophisticated Uprev is, but when I had the HP tuners program for my LS3 corvette virtually every parameter in the areas of fuel, timing, temps etc was programmable by minute blocks within the program. The chart below is the high octane timing table. Each block can be manipulated. You also had MAF scaling which, in conjunction with the logging function and a wideband A/F gauge, allowed very precise tuning. It's my understanding that the Long term trim corrections are added to the WOT fuel map. This is why the reported A/F's (with the correct SG readings) are slightly rich...
Rich is better (and safer) than lean but doesn't make quite as much power which is why custom programming will show increases.
