IAT vs fuel WOT, how to compensate?

Hi,
actually my wideband is not working so i'm relying only on narrowbands mV.
When i tuned the car with wideband for 12.5AFR at wot i was at 860-865mV narrowbands average value at IAT 50°F (tested on February-March).
With IAT 70°F i was at 850mV (tested on May), now today with IAT 90°F i'm at 840mV so my understanding is that i'm lean a little with the increase of IAT..

What table can i use to compensate the fuel vs IAT?
I'm thinking the table with injector flowrate vs IAT to put something like 0.990 at 86°F and above to increase 1% fueling (it should state the flowrate is smaller than 1% so it will increase by 1% everything) but i though there should be a table for airflow vs IAT under airflow....i've seen there is cylinder charge temperate and some table with IVT like openloop gain but not sure...

Any suggestion?
Thanks.

My Car is a Corvette c6 ls2 with 1-3/4 LT headers,fast102,borla touring, k&n.

The bias table you're talking about is for SD only to reference IAT vs. ECT for proper fueling, otherwise you'd be lean/rich depending on air temp, MAF doesn't need that table.

The IFR vs. IAT you should not need to alter much, and especially if you are running with narrow bands, I wouldn't be trusting that data too much if I were you, although with NA seems to work okay.

With increase in IAT generally yes you would nee to add a little more fuel to get your fueling in line but thats only because when it gets hot, you will have your fuel evaporting when it hits the valve at low RPM, I would play with your EOIT (end of injector timing), as car gets hotter, move the EOIT to a later point, so in GEN 4s that usually means taking out degrees so ie. instead of 100, move to 90*, that way since the intake start to get hot, you delay your injection event to later so you dont get the evaporating effect to a point where you have to start adding fuel to compensate.

Once you get that figured out, you can alter your IFR vs. IAT slightly, I find at 30* take out about 1% from IFR vs. IAT so .98-.99 works good to add fueling, then from 30-40* C take off another 1% or 2.

Don't concern yourself too much with IAT's when you're ideling, as soon as you start moving those IATs will drop, and at WOT your IAT's will generally drop, and on decel your IAT's increase due to closed throttle blade, opposite happens with ECT.

If you do the EOIT, you might want to maybe add to that table with RPM increasing, although it doesn't generally make much of a difference, but say 2k-3k add back 5*, 3-4k add back another 5* as fuel doesn't have much time to evaporate with higher RPM so you dont need to delay it as much, then after 4krpm doesn't really matter anymore since your injectors are almost always open, so carry the 10* total-add all the way up from 4k

The problem i see is that if i add 1% fueling by changing to 0.99 the ifr vs iat table starting from 86F, it will change also the fueling at all engine conditions because of this table is not linked to RPM. I would like to add 1% at wot or at least over 4000RPM in order to compensate my wot fueling due to the changing of IAT.
If i add 1% to high f maf value, then when IAT is below 60F i will be too rich.
Narrowband signal was verified before according to a wideband on previuos logs so i can trust on that value, i need to get the value back at wot at 860mV of average to be in the range 12.5-12.8 verified before

I wouldn't be relying on a narrowband sensor to have that kind of fidelity and consistency. The variances may be indicative of change, but there's no way you can make the relationship between 860-865mV always equalling 12.5AFR. The sensors are highly temperature and pressure dependent, often the exact same fuelling on back to back WOT runs will result in variances in NB voltage. I am not saying you haven't leaned out some, I am just saying you cannot expect that kind of accuracy from a NB at that end of its output, exaggerated by utilising LT headers, otherwise none of us would bother with widebands.

It's a ballache, but this is obviously a car you have time to devote into, have you considered trying to remodel the cylinder charge bias? A little less bias towards the IAT at higher airflows might help you out some. The issues is once you change this table, you end up like a dog chasing his tail as the VE technically requires massage and so the circle continues. In any case, good luck!

860-865 mV was an average value on more than one log...that is why the error should me minimal.
I think actually i should be above 13AFR with average less than 840mV...this going back to my previous logs and comparing wideband readings with narrowband readings.
Also i have experienced at wot some small knock that i don't know if they are holes on the street or not...
What i will do is to put on IFRvsIAT 0.99 86°F and 0.985 or 0.98 from 104°F and above. Also on IAT base spark compensation under 86°F insert -0.5° from 0.72 to the end just as additional safety purpose.

Then i will do other logs and see the results, i do prefer to have more safety features.
I have 91octane and wot at about 20°

something very strange...i tried as per above...i did three different logs...IAT 90°F...LTFT VE are a little richer than before so it means it is ok but despite of what i though, at WOT it is worst, i'm around 820mV now...i don't understand why...if i say to the ECU my flowrate is 0.99 it should be increased of about 1% at all conditions...so why i'm leaner than before at wot???

Don't touch timing too much for idle /low rpm purposes, first by advancing timing you will slightly lean out the mixture, just slightly.

Second, if at idle your IAT is hot, as mentioned above, as soon as you start moving your IAT's will drop.

By lowing your IFR in IAT so .99 makes the mixture richer, 1.01 makes it leaner, again IAT will be hottest while sitting idling with throttle closed, soon as you start moving it drops.

Keep in mind if you're trying to fine tune your low rpm values with this, you'll be dissapointed as there is much more that happens which effects your low rpm fueling with temp conditions than IFR tables, just copy the table from an LS9 engine if you want. I did because my IAT is inside the intake after the TB.

Why are you talking about idle or low rpm?
I'm referring only to wot operation. At costant 90F IAT i don't understand why putting 0.99 in IFRvsIAT i've leaned the mixture...it should be richer..

Is it SD or MAF? If you are running a MAF then temp has no bearing since the temp is baked into the MAF reading. It measures airflow/sec which includes density in that which is all the air temp would be adjusting. I def wouldn't be basing my fueling off narrowbands either. They are not accurate at all under rich conditions and the warmer ambient temps alone will affect how the narrowbands read. Get a wideband back in it and see what it's doing. Chasing a decimal point on a wideband isn't gonna make a difference on a standard street car.

Get a wideband , it richens up for me in all conditions when I lower WOT or cruise or Idle..

don't know why but resetting the fuel trims changed the starting value at wot of my narrowbands for some miles...
Changing the injector flow rate vs IAT i can say it is working and after some logs i reached 870mV average with 0.994 at 86°F and 0.989 104°F with measured IAT during the logs from 84°F to 103°F...