MicroSquirt.com read only forum (Jan.15,2018)

Hi All.

What is the point of this Single or Dual Table?

Is it just so I have have a bigger RPM range?

i.e going from: (Table 1) 600,1100,1500,2000,2500,3000,3500,4000,4500,5000,5500,6000

to: (Table 1) 800,900,1000,1100,1200,1300,1400,1500,1600,1700,1800,1900
(Table 2) 2000,2500,3000,3500,4000,4500,5000,5500,6000,6500,7000,7500

Or have I got the wrong end of the stick.

Thanks for your time.

For ALMOST everyone, table one maps to both banks of injectors.
So PW1 = PW2

As I understand, the second table would mainly be used for staged injectors (more than one injector per cylinder). Were you might want a second set of injectors at high power for example.

I suppose if you had a two cylender engine you could also tune each cylinder to its own VE table. Or perhaps on a "V" engine with seperate manifolds you would use it... but I'm just a wimpy 4-banger so can only speculate. I though of using it to inject methanol/h2o at high boost... when I think the bottom end can take it

When Guy and I originally implemented it, he was going to use it for progressive nitrous and I was going to use it for proportional water injection. Roger used it for staged injection on his rotaries for a while, then developed a better staging algorithm. Some of the Probe/MX6 guys use it to do bank trimming on their V6s that apparently have an intake manifold that delivers more air to one side, thus making this a useful thing to do.

If you want a greater spread of RPM on one VE table, just change the RPM bins, I really can't see having bins 100 RPM apart, that would just be a nightmare of tuning, with no real benefit.

Eric

Is is also handy (As I understand it) to run engines in a 'V' configuration with 2 oxygen sensors. one table controls one bank using one O2 sensor while the second table is used to control the second bank with the second O2 sensor.

darkstarmedia wrote:Is is also handy (As I understand it) to run engines in a 'V' configuration with 2 oxygen sensors. one table controls one bank using one O2 sensor while the second table is used to control the second bank with the second O2 sensor.

It is true that this is what the Extra code does, but I forget why it requires DT to do it. Surely we could apply ego correction differently to channel 1 and channel 2? (I ask in a semi-rhetorical manner)

James

jsmcortina wrote:It is true that this is what the Extra code does, but I forget why it requires DT to do it. Surely we could apply ego correction differently to channel 1 and channel 2? (I ask in a semi-rhetorical manner)

James,

I'm guessing that the reason for having two sensors is because the two banks need a different tune. If that's the case, then you'd want dual tables to set the base for each bank differently, and not make one lambda correction do all the work of trimming out the one "off" bank...

Eric