What to Tune First

[SSpdDmon]

Depends on your method of tuning. Per concept 1, you would use the same principles of the AutoVE tutorial and apply them to the MAF table. Per concept 2 (guys chime in if I misunderstood) you would accept your MAF table as a constant and tweak your IFR table.

Correct - assuming you have the right MAF table for the hardware you're running and you've dumped the B0120 threshold to something below normal operation (i.e. 100rpm).

[BrianC98Z28]

i understand how to do the autove but when you say use the same principles what exactly do you mean?? Can you use one of the MAF maps that efi already has i.e (im not on my comp with the software) so i dont remember exact titles but its something like MAF Configuration BEN LC1 or something like that and log the data with the maf reenabled and log that data and make the correction in the tune and smooth and then be good to go in that area or am i way off par here??

[joecar]

Brian, yes that is correct, you apply the MAF BEN map to the MAF table (using copy-with-labels and paste-multiply-with-labels).

[BrianC98Z28]

thanks joe just making sure i understood it right

[VTC_WS6]

Has anybody found their OE MAF's to be in need of extensive calibration as is? I ask because I at this point of MAF is stock and I'm not really sure if I stand to benefit from MAF adjustments or am I just 'over complicating' things?

[jfpilla]

Brian,
I think part of your question was missed. Remain in SD when logging B5001.
Joe

[VTC_WS6]

Brian, yes that is correct, you apply the MAF BEN map to the MAF table (using copy-with-labels and paste-multiply-with-labels).

By 'MAF table' you are refering to B5001 correct?

Side question, with all this tuning of the MAF I got to thinking and I'd like to confirm what I belive to be correct. As I understand it, If one were to drop the MAF threshold for calc. (B0120) to say 100rpm, you basically force the PCM to use the MAF sensor exclusivley for airflow calculation. Now you can set CL enable (B4205) to a higher than expected limit (say 122*C) and you now for the PCM to operate in OL. At this point I assume two things, first the PCM will derive fueling calculations from B3605 (when not at WOT/PE mode) exclusivley, with actual fuel delivery being influenced by the IFR table of course, and secondly, one could at least theoretically set the EQ modifier for the PE tables to '1.00' (or just disable PE mode altogether) thereby making B3605 the sole source of fueling calculations at all times. No MAP, no VE, no O2 input.

Now i'm not saying this is the 'right' or 'wrong' way to do anything, I'm just trying to get a better grasp on exactly how the PCM logic operates on a basic level.

[VTC_WS6]

Depends on your method of tuning. Per concept 1, you would use the same principles of the AutoVE tutorial and apply them to the MAF table. Per concept 2 (guys chime in if I misunderstood) you would accept your MAF table as a constant and tweak your IFR table.

Correct - assuming you have the right MAF table for the hardware you're running and you've dumped the B0120 threshold to something below normal operation (i.e. 100rpm).

But how exactly are you logging the IFR? I read:

IFR Table {B4001}: Based on what you believe to be true about your injectors, you should use the IFR spreadsheet RedHardSupra made available on his website (or a similar one) to initially set this table. Then using the reciprical of your BEN factor for your WBO2 along with the MANVAC pid, you'll correct this table. Remember, raising values lean out AFRs and reducing values richen AFRs in this table. This will become an important constant that you will base the rest of your tune on.

..I'm just not understanding what you are actually logging? When I open a new map in Scantool for example, I use the MANVAC pid as my row, use the BEN LC1 factor as the data but what am I using for the column, and how is the commanded AFR not influencing the final amount of fuel injected? Or should I be setting the same commanded AFR for an entire section of B3605 (say setting all rows 60-80*C ECT at 12.5 AFR) and then driving the car and hitting as many vacuum points as I can and then using the difference in commanded AFR and actual AFR to set the IFR amounts? (Did I just answer my own question? )

[BrianC98Z28]

Brian,
I think part of your question was missed. Remain in SD when logging B5001.
Joe

You stay in SD when dialing in the maf?? I thought youd dial it in with it reenabled, because in SD its disabled.

[Kurtomac]

dumb guy input....if you were not in SD wouldnt your fuel trims start jacking stuff up vi the 02 sensors