I'm just wondering if wot fueling changes need only to be changed in the pe vs. rpm tables or also in the open loop multiplier table. I have my car at 94% pe and the 02s show 940-950 and I have a little knock retard around 3500-4000 with the stock timing. Shouldn't 6% percent of leaning it out reduce the 02 numbers more. Before I did any tuning at all i had 02's about 945 with 0 KR at all. thanks for the help!
98 M6 TA, mods: tsp torquer(233/233 .589 112), Patriot golds, ls6 oil pump, ls6 intake, tsp lid, pacesetter LT\'s and ORY, magnaflow, fra, HPTUNER!
I only mess with PE vs. RPM and haven't read anything about open loop.Originally Posted by luv2spd
Do you have long tube headers?? I do, and don't think my o2s are accurate at WOT due to being further downstream.
In other words, I think 890 o2 would be WAY lean in my car. Right now, at 93% PE, I have zero KR, 28* of timing, and 940/920 o2 readings at WOT.
2002 Trans Am 6sp, Hurst shifter, short stick,
!skip shift, SLP lid, Holley filter, Dynomax Ultraflow muffler, Jet Hot long tubes and cats, FRA, HP tuners, Hotchkis STB and LCAs. TEA stage 1.5 5.3 heads, Comp 220/224 114 +2, UMI Boxed SFCs
Yeah, I do have long tubes. I was at 94% pe and the 02's were still around 950. Before any tuning they were about 945. Does the ifr table make wot tuning richer since i mult. the ifr by 94%?
98 M6 TA, mods: tsp torquer(233/233 .589 112), Patriot golds, ls6 oil pump, ls6 intake, tsp lid, pacesetter LT\'s and ORY, magnaflow, fra, HPTUNER!
Yeah, with long tubes, I'm afraid the o2 readings are less accurate than without.
Although, mine are pretty consistent. They just may be off by a factor of 30 or 40. I wish someone who's dynoed their A/F with longtubes could tell us what they're o2s are reading.....
The way I understand the IFR table, it does make you run richer. So, multiplying 94% and 94% PE would just get you to where you started.
2002 Trans Am 6sp, Hurst shifter, short stick,
!skip shift, SLP lid, Holley filter, Dynomax Ultraflow muffler, Jet Hot long tubes and cats, FRA, HP tuners, Hotchkis STB and LCAs. TEA stage 1.5 5.3 heads, Comp 220/224 114 +2, UMI Boxed SFCs
IFR is meant to represent the injectors' fuel
delivery. If you scale it by 0.940 the PCM thinks
it should shoot 1.064X the pulsewidth to deliver
the "right" amount of fuel.
PE is one source of enrichment. When you
exceed the MAP threshold, PE calculated fuel
shot becomes one of the options.
Open Loop F/A table is another enrichment
source. It is also calculated for your MAP
operating point and ECT. Any time the engine
is open loop (including PE) this table also is
an option.
The fuel shot decision uses the richest of the
options that are "legit" at any point in time.
So if you were over PE threshold, and PE said
0.94 (a commanded 15.6:1 AFR) it might just
ignore it, because even the regular closed loop
target is fatter. The Open Loop table is also
fair game at WOT and its 1.13 value is the
fattest and probably what will get picked; PE
values less than the Open Loop table, 80-
100kPa values, probably will have no practical
authority (unless the OL table is similarly
reduced).
940mV is way pudgy. Unlikely that you have a
fuel system that over-delivers by that amount
unless you changed the injectors. If you didn't
then there is something else going on and may
be a better way to represent it than IFR scaling.
IFR is a handy handle with not so many side
effects, but a band-aid isn't always what the
doctor ordered.
Leaning out PE has some effect on LTFTs, from
what I've seen. If you messed it around lean, the
LTFT "bins" above PE MAP threshold may have to
reacquire and meanwhile will ping a bit. Are you
clean there, to begin with, trimwise?
Well, my part throttle is pretty much down. I have it so they lock at 0 at WOT. I don't like that i have to have some cruising cells so negative though. Like in cell 6, i believe, the ltft is -9 while cell 15 is only like -1 or something. What else should I do? I have the stock maf and maf ends.
98 M6 TA, mods: tsp torquer(233/233 .589 112), Patriot golds, ls6 oil pump, ls6 intake, tsp lid, pacesetter LT\'s and ORY, magnaflow, fra, HPTUNER!
ttt
98 M6 TA, mods: tsp torquer(233/233 .589 112), Patriot golds, ls6 oil pump, ls6 intake, tsp lid, pacesetter LT\'s and ORY, magnaflow, fra, HPTUNER!
Are these average numbers for the cells?
Honestly, I didn't go that much into detail with my LTFTs. I got them barely negative at part throttle and cruise (average -2 and -3), Idle was slightly more negative (-6), and they vary a little based on the weather.
Either way, they're 0 at WOT, and don't go positive at any point. So, I don't really think it matters other than that.
Someone could correct me, but I don't think -9 will hurt you or anything.
Now, start messing with your PE vs. RPM for WOT fueling.
2002 Trans Am 6sp, Hurst shifter, short stick,
!skip shift, SLP lid, Holley filter, Dynomax Ultraflow muffler, Jet Hot long tubes and cats, FRA, HP tuners, Hotchkis STB and LCAs. TEA stage 1.5 5.3 heads, Comp 220/224 114 +2, UMI Boxed SFCs
i still have the stock injectors. could you clarify what you mean in the above quote? thanks
98 M6 TA, mods: tsp torquer(233/233 .589 112), Patriot golds, ls6 oil pump, ls6 intake, tsp lid, pacesetter LT\'s and ORY, magnaflow, fra, HPTUNER!
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