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Transients and Scaling Pecentage

Posted: 2023 Feb 05, 13:27
by Killer95GT302
Does anyone know which transient fuel functions/scalars are supposed to be scaled when scaling the tune for larger injectors? I have a feeling I'm missing one of these.

Re: Transients and Scaling Pecentage

Posted: 2023 Feb 05, 17:18
by decipha
fn1321 the tseif table

its got sp**

all scaling percentage values do

Re: Transients and Scaling Pecentage

Posted: 2023 Feb 06, 10:08
by Killer95GT302
Thanks - do transients end up as part of the calculation for LAMBSE, or is the transient value something calculated and used in the background?

I have a tip-in/out issue I'm trying to figure out if its transients or something else. Right now on a sharp tip-in/out (like quick rev) I can see the LAMBSE go way low, AFR goes rich, then it goes way lean even though LAMBSE is not commanded lean, in fact it stays < 1 until AFR stabilizes.

Re: Transients and Scaling Pecentage

Posted: 2023 Feb 06, 12:46
by decipha
background

that could be anything but tip out isnt important enough to matter

Re: Transients and Scaling Pecentage

Posted: 2023 Feb 07, 16:46
by Killer95GT302
Tried messing with this in open loop - So I found that the LAMBSE is commanded based on the calculated PERLOAD. I appear to be hitting a pretty high load when stabbing the throttle (in some cases 70 LOAD between 1000 and 1500 RPM) which is causing it to calculate a richer LAMBSE based on fuel table FN1362 and FN035.

I can mess with values if I want I guess to get that under control, and I did to some extent - what I found that I thought was weird was that when I changed things around to have a LAMBSE closer to 1.0 when stabbing the throttle (instead of .88 before), the amount it went lean afterwards also went down. So less fuel went in when stabbing it, but also the amount it went lean afterwards came down too, by about 2 AFR points.

Is there some voodoo going on in the background with transient functions looking at HEGOs even in open loop that see "hey it didn't go that rich, so we don't need to pull as much fuel" - that's the behavior I'm seeing anyways.