[ride5000]

Originally Posted by Christian.

FWIW, I would just focus on fueling in Lambda...it really makes tons more sense, is easier to tune with, and will make life easier.

frankly i don't think it makes a bit of difference whether we are talking about afr or lambda.

why?

because NONE of us are REALLY talking about air fuel ratios.

we ALL talk about indicated afrs via a wideband o2 sensor that measures leftover oxygen. the wideband itself is what converts this to an indicated afr. on my tuner pro i can tell it to display lambda=1 as any number i care to type in.

the question that must be asked is, are we targeting an actual air mass to fuel mass ratio, or are we targeting a leftover o2 level.

if it is the former than we are all using the wrong tools to measure the results, and we should all be looking at the fuel (whatever that fuel may be) specific gravity, the injector pulse width, and the mass air flow--and nothing else.

if it is the latter then our desired indicated wideband display of afr should not change one bit.

[ride5000]

Originally Posted by nhluhr

Is it better to change the injector scalar to a 6.3% lower flow number or to change something else (MAF cal, fuelmap, etc) to help account for E10 fuel?

I am using Enginuity on a mostly-stock 06STI.

It makes sense to me that I still want my lambda targets to be almost the same, so I don't want to change the whole fuel map to try to account for this but instead to just reduce the scalar to increase fuel flow overall, including closed-loop.

Also, I'm having trouble finding where to alter the closed-loop fuel targets in Enginuity. What am I missing?

nick, i would without a doubt change the injector scaling value. once your fuel trims are between -5 and +5% i'd call it done.

for the life of me i don't know why people with stock maf tubes, stock maf sensors, and stock air filter housings are so quick to change the mafv-g/s translation table.

[ZuMBLe]

There should be no reason to change that table with stock parts. Except maybe if you change the injectors.

Originally Posted by ride5000

nick, i would without a doubt change the injector scaling value. once your fuel trims are between -5 and +5% i'd call it done.

for the life of me i don't know why people with stock maf tubes, stock maf sensors, and stock air filter housings are so quick to change the mafv-g/s translation table.

[WolfPlayer]

Originally Posted by ZuMBLe

There should be no reason to change that table with stock parts. Except maybe if you change the injectors.

I *think* I disagree.

Another reason to change the MAF tables on a stock setup is to get your actual wideband lambda value to agree with the lambda value in the fuel table for open loop areas. This assumes that your car is in good working order and the that deviance is due to the fueling necessary to achieve the specified lambda.

t

[TheMadScientist]

Originally Posted by ride5000

for the life of me i don't know why people with stock maf tubes, stock maf sensors, and stock air filter housings are so quick to change the mafv-g/s translation table.

I would calibrate not "tune" the MAF table even on a stock car. There is enough variance from car to car to warrent the cal, even on a stock airbox.
I would not use the MAF table to tune the fueling at all. The MAF is a reference, you want that reference to be as acurate as possible to the acual airflow.
When a tuner changes the MAF table you get what seems like a ton of air through the MAF when you log it. The log will say Xg/sec but in the real world the car is really only flowing X-Yg/sec. I have seen a log of a VF40 that says it is pulling +300g/sec because the tuner used the MAF table as coarse fuel tuning then "fine tuned" the fuel map. IMO a vf40 will NEVER flow +300g/sec.

TMS

[WolfPlayer]

Originally Posted by TheMadScientist

I would not use the MAF table to tune the fueling at all. The MAF is a reference, you want that reference to be as acurate as possible to the acual airflow.

So, 2 questions on this one ...

1) How do you propose to set the MAF tables to the actual airflow in the upper MAF Voltage area?

2) Would you adjust the upper voltages in the MAF table in order to get the actual lambda to agree with the fueling lambda? I would - and this is how I would calibrate the upper area of the MAF table. I calibrate the lower area according to the fuel trims. Calibrating the upper area based on lambda is that same exact thing because you are just trying to get the MAF airflow to produce the specified lambda.

t

[TheMadScientist]

Originally Posted by WolfPlayer

So, 2 questions on this one ...

1) How do you propose to set the MAF tables to the actual airflow in the upper MAF Voltage area?

2) Would you adjust the upper voltages in the MAF table in order to get the actual lambda to agree with the fueling lambda? I would - and this is how I would calibrate the upper area of the MAF table. I calibrate the lower area according to the fuel trims. Calibrating the upper area based on lambda is that same exact thing because you are just trying to get the MAF airflow to produce the specified lambda.

t

#2 exactly. But that is calibrating the MAF to show the ECU the correct amount of air flow so it hits the AFR in the map. Now I have seen a tuner use the MAF table as coarse fueling tuning, that tuner did not match the upper/lowwer part of the MAF curve to AFR. He just kept movinng the entire MAF curve to the fueling where he wanted it, the AFR in the fuel table did not match at all what was at the tail pipe.

TMS

[R4ND0M_AX3]

Originally Posted by ride5000

...we should all be looking at the fuel (whatever that fuel may be) specific gravity, the injector pulse width, and the mass air flow--and nothing else.

you still need to know the fuel pressure and injector delays (which also requires knowledge of the battery voltage).

I don't feel comfortable quoting AFR numbers from a lambda sensor that thinks a different fuel is going through it. I'm already seeing threads were people are using meth and talking about their fuelling and not mentioning if their AFR numbers are 'actual' or petrol only based.

[ride5000]

Originally Posted by R4ND0M_AX3

you still need to know the fuel pressure and injector delays (which also requires knowledge of the battery voltage).

you get my point: afr, in the strictest, most "proper" sense of the term, is based off of the mass ratios of air to fuel.

it does not take into account either the oxygen content of the air, or of the fuel.

i look at leftover o2 and egts when i tune my car, because those are the only two things i have proper instruments for.

[LOLSTi]

Is there merit in a practical (not theoretical) sense of using the MAF vs. Fueling values as tuning (tools? seems too redundant to be a tool) references?

Are we simply running into a language issue or am I misunderstanding something completely?

[WolfPlayer]

Originally Posted by LOLSTi

Is there merit in a practical (not theoretical) sense of using the MAF vs. Fueling values as tuning (tools? seems too redundant to be a tool) references?

Are we simply running into a language issue or am I misunderstanding something completely?

IMHO, the only reason to use the MAF tables for fueling is the following ...

A) To make the actual lambda value agree with the target lambda value. This is another way of saying that you must calibrate the MAF table for the MAF that you are using in order to allow the car to achieve the desired AFRs.

B) To smooth out idle-RPM oscillations due to big injectors/MAFs

t

[LOLSTi]

Thanks T.