Hey Guys,

Sorry for the big image, but its easier to see what I'm talking about.

Initially I thought it was a miscalibrated WB, but after 4 different calibrations (car off for 12 hours in-exhaust calibration) I still get the same results.

So the question is, does my Fuel Map look about right for those AFR's I am getting.

If I lean out the Fuel map by 1point (to get my desired AFR of 11.7) the fuel map looks pretty dangerous - ie too lean!

Any comments welcome!



Mods: frontpipe (you call it a down pipe), ralliart filter, 3port GM to hold about 20psi of boost, super duper MIVEC map. LEANSPOOL is OFF!

Cheers
D.

 

I should mention that apparently if you do a calibration and the air ISN'T free then the WB will read richer on the rich side of stoich and leaner on the lean side of stoich.

Hence why I thought my WB was out, because an AFR of 10.7 is pretty rich for that fuel map - I think neways

 

If your injectors are scaled correctly and your fuel trims are correct, it doesnt matter what the numbers in the fuel are, as long as your wideband reads what you want and you arent knocking.

Because of the vast amount of meth that I run, some parts of my fuel map are leaned out (numbers wise) to 16.0 but Im readin 11.4 on my wideband.

 

yeah fuel trims are correct!

understand your point about fuel map numbers being irrelavant, however I would have thought cars with the same mods should have the same numbers (within say 0.3)

 

That fuel map looks too lean to me for the mods you have.

Are you running an innovate? Be sure to ground it correctly.

 

yeah thats what I'm worried about.

LC1 - Its grounded properly!

I am going todo a proper free air on it, as well as fix this exhaust

 

As far as I know, a mis-calibrated wideband will always read leaner than actual. The only time it would read richer than actual is if it was too close to the exhaust manifold.

Have you changed intake or injectors at all? New injector & MAF scalings would have an impact on the fuel map. Also, as the air warms up and gets less dense, the same fuel map will likely get progressively richer and richer, meaning you need to lean it out like you're doing now.

2 weeks ago, I was on the dyno and making perfect 11.5 AFRs, it was a cold day.
2 days later, it was very humid and muggy, probably a 15°F temp difference plus humidity... without any changes to my car, I was running 10.9, 10.8 AFRs on the same tune, same boost, same fuel, etc.

 

nope stock car except for the downpipe..

LC1 forums/support dude says richer on the rich side and leaner on the lean side.. what makes you think it will always read leaner?

did your loads change? it would be interesting to log the temp+baro corrected load in that scenario...

 

Well, if it's calibrated to think that free air is actually air with fuel in it... then it makes sense that it will be offset by that much throughout the whole lambda range.

I can't see how it would read richer than actual if you tell it "This air here which is loaded with fuel is actually perfectly clean, free air". That should only lead to false lean readings. Plus when a sensor is at the end of its life (exposure to a lot of leaded fuel, etc.) it starts to read too lean.

I could be wrong, though.

 

hrmm its hurting my brain...

 

what's your mod list ?

 

Mods: frontpipe (you call it a down pipe), ralliart filter, 3port GM to hold about 20psi of boost, super duper MIVEC map. LEANSPOOL is OFF!

 

tephra,

For your free air calibration, just do it coasting in gear with no throttle. The engine will pump enough free air to evacuate the exhaust nearly immediately. This will give you a good calibration.

Do this:

If you can find a downhill part of road, even better, if not, just do this:

1. Use one of the higher gears, like 3rd, 4th, 5th. You probably won't have enough road to get to the speeds necessary in 5th, but maybe 3rd or even 4th. 3rd may be safest.

2. So, let's say you are in 3rd. Do a pull up to near redline, then just let off the throttle...keep it in gear.

3. You should see your LC-1 flashing 20.9 nearly instantly. This is the LC-1 measuring 20.9 % O2 in the air. This is the time that you should calibrate the LC-1.

4. After you let off the throttle and the LC-1 begins flashing 20.9, give it a second or two to make sure that all gases are evacuated from the exhaust. Then, do your calibration before your RPMs drop to about 1500 or so, where the ECU will begin to fire the injectors again.

If you are going downhill, you will have a longer time, but even on a flat road, this is very easily doable. I have calibrated my LC-1 like this several times and it takes a matter of seconds, rather than having to wait overnight or longer.


Eric

 

looks a little lean but you should be ok

 

Yup ive seen that method on the forums, but how can we be sure it works? i suppose log IPW and so long as no fuel gets injected then the engine is just a big air pump...

this is all moot really because I need to get my leaky exhaust fixed first