Ok, any recommended values to enter in that table? Do you put values just slightly off stoich so stft are disabled, yet you aren't commanding a right value.
Ok, any recommended values to enter in that table? Do you put values just slightly off stoich so stft are disabled, yet you aren't commanding a right value.
Yes, choose either EQR 0.98 or EQR 1.02
( you will see those commanded )
I've got a question about this method of working with table B3647. If you set the low to mid kPa cells to something like 0.98 (mine is set to lambda, btw) and do the calibration of the VE table with these values, when you go back to setting those cells to 1.00, does that throw the STFTs off kilter? Is this enough to matter, or simply one of those inconsequential differences things?
Would it be better to set those cells to something like 0.999 instead to be as close to 1.00 as possible without triggering the STFTs into operation?
CorvetteFlorida.com
2002 Corvette Z06
427 RHS block built by LME
STS rear mounted twin turbos
It nearly died on the operating table, but I'm bringing her back.
I was also wondering this, but figured it would be only 2% off and that if my trims were only 2% off I'd be extremely happy!Originally Posted by Rich Z
BTW, I finally figured out what was causing the engine to surge. It was the throttle cracker B4309. In the idle tuning tutorial it says to add air the entire row at 400 rpms. Once i zero'd out row 400 it cleared up the surging.
No... you will see STFT oscillation get smaller and tighter... you will see your wideband do the same thing.
You have to remember that whatever EQR you're commanding, the BEN factor takes this into account...I was also wondering this, but figured it would be only 2% off and that if my trims were only 2% off I'd be extremely happy!
BTW, I finally figured out what was causing the engine to surge. It was the throttle cracker B4309. In the idle tuning tutorial it says to add air the entire row at 400 rpms. Once i zero'd out row 400 it cleared up the surging.
BEN = COMMANDED EQIVRATIO * WIDEBAND LAMBDA
( remembering that wideband lambda = 1 / wideband EQR )
B4309 TC... ok thanks for posting that.
I wanted to revisit this. I got the car back up and running and was doing more tuning on it. I have table B3647 setup as follows, however when logging commanded AFR or EQ it is commanding 9.71 (i'm running e85) or 1.00 EQ. Why is this?
I know when I first changed this table it showed in the logs a different commanded value, but for some reason it is now commanding a stoich value again... Any idea's? (I'm wondering if I have changed something else along the way that would affect it?) I have STFT disabled at idle, but am wondering if they are really disabled if on the logs it isn't commanding the correct value?
E85 stoich has stoich AFR 9.7 which corresponds to EQR 1.00, which also corresponds to Lambda 1.00 (lambda = 1/EQR).
i.e. EQR 1.00 is stoichiometric (the AFR depends on the fuel).
Avoid logging AFR, and log EQR and/or Lambda instead.
I should have been more clear. Earlier in this thread we were talking about changing table B3647 so that the values aren't at 1.0 EQR, this way STFT are disabled. The attachment in my last post shows the B3647 table with values of 1.02 EQR, yet in the logs it is commanding a 1.0. Attached is a screen shot showing the commanded EQR.
When logging the EQR and AFR commanded should not be at stoich since in B3647 I am commanding a value slightly off stoich (to disable STFT), so why am i seeing the discrepancy?
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