Need help with understanding MAF adjustments.

[Aint Skeered]

I am going to look at this again tonight and try them out. Not sure which way yet but if you can go more into detail on both methods as I dont understand what rinse and repeat meens or what you meen by setting AFR %error and extending the Maf curve.

Mr Prick, I have never tried messing with Rtacs, could you go a little further into what to do?

Thanks guy's., I am leaving work to go home. I will check back in a couple of hours . Thanks, Chad.

[mr.prick]

I have never tried messing with Rtacs, could you go a little further into what to do?

RTACS works with the RoadRunner LS1 Realtime Emulation PCM.

[Aint Skeered]

I dont have the road runner. thanks anyways.

[SSpdDmon]

I am going to look at this again tonight and try them out. Not sure which way yet but if you can go more into detail on both methods as I dont understand what rinse and repeat meens or what you meen by setting AFR %error and extending the Maf curve.

Mr Prick, I have never tried messing with Rtacs, could you go a little further into what to do?

Thanks guy's., I am leaving work to go home. I will check back in a couple of hours . Thanks, Chad.

Rinse/repeat simply means, after you go out and log your data, upload the new tune with changes and log again. Make changes and upload that new tune. By the 3rd time around, it should be pretty close.

As for further detail....all your doing is logging the parameters of the table your changing along with the data you need to make the changes. So, in this case, you'd log MANVAC, WBO2 AFR, and Commanded AFR along with the normal stuff. AFR% Error for IFR table = Commanded AFR / WBO2 AFR. That way, if you see 15:1 when you're commanding 12:1, the result would be 12/15=0.8....which is saying reduce that cell by 20% to keep the injectors open 20% longer. If it was the other way around (seeing 12 when commanding 15), it'd be 15/12=1.25.....which is saying increase that cell by 25% so the injectors only stay open 75% of the time they were. Make sense?

Since there's only a handful of cells in the IFR table vs. the MANY cells in the MAF table, it shouldn't take too long. One trick is to use your filters so that you're focusing on the data in the middle of the cells. In other words, for the 35kPa cell, I'd filter out any data above 36kPa and any data below 34kPa. Filter out any transitional throttle (TP% is changing more than 3% over 500ms) along with any lower airflow scenarios (i.e. RPMs less than 1800 or so). You'll see the new IFR shape start to take place...

[mr.prick]

As for further detail....all your doing is logging the parameters of the table your changing along with the data you need to make the changes. So, in this case, you'd log MANVAC, WBO2 AFR, and Commanded AFR along with the normal stuff. AFR% Error for IFR table = Commanded AFR / WBO2 AFR. That way, if you see 15:1 when you're commanding 12:1, the result would be 12/15=0.8....which is saying reduce that cell by 20% to keep the injectors open 20% longer. If it was the other way around (seeing 12 when commanding 15), it'd be 15/12=1.25.....which is saying increase that cell by 25% so the injectors only stay open 75% of the time they were. Make sense?

this is good advice for {B4001},
a calc.pid comes in handy here commanded/actual ("reverse BEN factor").
to overcome a rich condition with {B4001} you must increase the values and,
vice versa for lean.
also you can change {B3701} with BEN, which may be easier for you.

IMO
it is easier to alter {B0101} to a set {B4001} than the reverse.

[joecar]

Good points... B4001 is in "reverse"... increase B4001 to go leaner.

[Aint Skeered]

Rinse/repeat simply means, after you go out and log your data, upload the new tune with changes and log again. Make changes and upload that new tune. By the 3rd time around, it should be pretty close.

As for further detail....all your doing is logging the parameters of the table your changing along with the data you need to make the changes. So, in this case, you'd log MANVAC, WBO2 AFR, and Commanded AFR along with the normal stuff. AFR% Error for IFR table = Commanded AFR / WBO2 AFR. That way, if you see 15:1 when you're commanding 12:1, the result would be 12/15=0.8....which is saying reduce that cell by 20% to keep the injectors open 20% longer. If it was the other way around (seeing 12 when commanding 15), it'd be 15/12=1.25.....which is saying increase that cell by 25% so the injectors only stay open 75% of the time they were. Make sense?

Since there's only a handful of cells in the IFR table vs. the MANY cells in the MAF table, it shouldn't take too long. One trick is to use your filters so that you're focusing on the data in the middle of the cells. In other words, for the 35kPa cell, I'd filter out any data above 36kPa and any data below 34kPa. Filter out any transitional throttle (TP% is changing more than 3% over 500ms) along with any lower airflow scenarios (i.e. RPMs less than 1800 or so). You'll see the new IFR shape start to take place...

so at 100kpa it is at 13.67 when commanding 12.0 , that is 12%out so I would subtract 12% from what I already have subtracted .

That is just a question, I am going to take a look at the logs and see if i have what I need.

Thanks.

[Aint Skeered]

Good points... B4001 is in "reverse"... increase B4001 to go leaner.

That is how I have been doing it, Learned that after getting efi live and that is how Futral had my trans am tuned from IFR tables.

[SSpdDmon]

so at 100kpa it is at 13.67 when commanding 12.0 , that is 12%out so I would subtract 12% from what I already have subtracted .

That is just a question, I am going to take a look at the logs and see if i have what I need.

Thanks.

Again - keep in mind 100kPa on the MAP sensor is probably 0 or 1kPa in MANVAC. MAKE SURE YOU'RE USING MANVAC AS A REFERENCE WHEN ADJUSTING IFR!!! So, assuming you're commanding 12.0:1 at WOT and you're seeing 13.67:1, you would adjust the 0kPa cell of IFR down by 12.2%.


MAVNAC 0kPa = WOT
MANVAC 75kPa = idle

[Aint Skeered]

I am not using the long term fuel trim pids in my black box as my nova that I am tuning does not have narrow bands. Could I take them out of my options ini and replace them with manvac?

Another question, can you log wideband through serial cable in pass through mode yet?