- Mon Mar 04, 2024 5:46 pm
#67396
Read through your past, we are on the same page, just stated differently.
PSIG wrote: ↑Mon Mar 04, 2024 5:08 pm I see a gap in concept, and I hope you will give me an opportunity to offer a different mind-set of the concepts.Right there with you. Not tuning to lambda/AFR, but these readings corroborated with spark plugs, mean a lot. If the plugs start to come out closer to what I expect, fuel and timing is getting to where it should be.Rednaxs60 wrote: ↑Sun Mar 03, 2024 5:08 pm… I went up/down the VE table cell values and had to lean out the cell numbers, not much but noticeable.Why did it need leaning-out? What was your goal? Why did you think it was rich of something? What something is that? Why is important to the concept.
No worries on this one, fumes in garage, and eyes burning.
Rednaxs60 wrote: ↑Sun Mar 03, 2024 5:08 pm… I know the fueling is "rich", so my options are to reduce the amount of fuel - VE table cell changes (maybe complementary change in timing - retard), or give the fuel charge more time to burn (advanced timing).Yes, to a goal. I see a small but significant gap in concept. It says OR instead of AND. If you adjust one you adjust the other, each + and - to find optimal values with data, because fuel and spark work as a team. What optimal values? That depends on the goals at that point of operation. Adjust your mindset from rich or lean to optimized. "I know it's rich lean not optimal, and I need to find the fuel and timing values it is optimal."
Always about relationships, to get the engine tune as smooth as possible and MAP lowest. Lambda/AFR readings observed for possible table changes.
Rednaxs60 wrote: ↑Sun Mar 03, 2024 5:08 pmWill pick a set of parameters (engine RPM, Gearing, Speed), adjust VE first, then timing for that specific set of parameters before moving on.Yes! But adjust to what? Adjust to the goal for that point of operation. We can have many goals, but one goal is primary at a specific point.
For most general applications, the goal for initial tuning is peak efficiency for either torque (power) or economy. Pick which one fits there, and tune (using data) to achieve that goal, at that point. There are other goals and efficiencies, but we're not there yet, and set our base tune on those two as a baseline. Modify for other purposes after the tune foundation is built.
In the generic example table below, note areas 2 and 3 have max torque as the typical goal, and the other areas do not require max torque and so are targeted for minimum fuel consumption. Some efficiency is always maximized, and if it's not torque we need, then it's economy to gain. We tune with data to find max torque fueling and timing to support it, or max economy fueling and timing to support it, for every point on the tables.
You pick which goes where for your purposes, goals, preferences, etc. Print a copy of your table, and mark or highlight every cell for which goal each cell will have - torque or economy. Tune each area for that chosen goal. That's job one. Crawl before you walk, and walk before you run.
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Rednaxs60 wrote: ↑Sun Mar 03, 2024 5:08 pmTake note of the lambda/AFR readings and if reasonable, adjust AFR table.Reasonable for what?You see where we're going with this at every point. To repeat, we never tune or adjust to an AFR. Get "adjust AFR" out of your head. We only tune to the chosen peak efficiency, then read what AFR that peak efficiency produces. The result of our tuning to peak values. Enter that value into the AFR Table , in order to maintain that best value you found in the future. Repeat in a new area. Connect the dots.
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Ernest Nash
Victoria BC
"Resistance is Futile"
"This is not a motorcycle project, it's my retirement career"
Victoria BC
"Resistance is Futile"
"This is not a motorcycle project, it's my retirement career"