VE Tuning for boosted cars, can it be done using the 105 MAP reading?
02-21-2004, 07:56 PM
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VE Tuning for boosted cars, can it be done using the 105 MAP reading? What do you guys think. Really, if you're in boost you're probably at WOT, so could you use the VE table to tune for wide open throttle stuff? Strange, though, just FYI...
I went to see what would happen if I took the VE table and scaled it up about 130% on my friends Z06 only in the 105 MAP area...IT RAN MUCH LEANER?????
Does that make any sense at all? I know there are arguments all the time about if the VE tables are used all the time, but we went back to his regular tune, A/F right on the money. Back to the VE table change tune, and it's lean again. According to everything I've ever done with FAST and DFI systems, if this table is indeed used by the LS1, the car should have run richer.
Any clues? Can the VE table be used to really help boosted cars that are maxing out the MAF? This particular car maxes the MAF out at 4800rpm.
I went to see what would happen if I took the VE table and scaled it up about 130% on my friends Z06 only in the 105 MAP area...IT RAN MUCH LEANER?????
Does that make any sense at all? I know there are arguments all the time about if the VE tables are used all the time, but we went back to his regular tune, A/F right on the money. Back to the VE table change tune, and it's lean again. According to everything I've ever done with FAST and DFI systems, if this table is indeed used by the LS1, the car should have run richer.
Any clues? Can the VE table be used to really help boosted cars that are maxing out the MAF? This particular car maxes the MAF out at 4800rpm.
02-23-2004, 12:15 PM
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I've been playing with VE on my N/A truck. I have seen similar results to what you describe. Increased the VE by 8% in some WOT-only cells and the O2s (and KR) say I went leaner. Also noticed that VE changes seem to have the expected effect on part throttle fueling. So at PT, a ~1% VE change means a ~1% fueling change. But at WOT, why does increased VE mean less fuel?
Perhaps the fueling calculations at WOT rely less on VE and more on something else?? Is the commanded AFR affected by VE changes? (my PE table doesn't change, but perhaps what the PCM thinks is 12.2AFR changes...)
Perhaps the fueling calculations at WOT rely less on VE and more on something else?? Is the commanded AFR affected by VE changes? (my PE table doesn't change, but perhaps what the PCM thinks is 12.2AFR changes...)