is this a good method for tuning my MAF?

[boomer]

Ok, i've been trying a few different methods and am getting slightly different results every time. now i'm not sure whats the best method for my G8. I have tried to read other threads and guides but am still not sure. especially since i dont have a true VE table, so i'm not tuning the VE table.

Should i first use my wide band to to dial in my commanded PE AFR via MAF AFR error? Like 7000Hz+ (with disabled LTFTs in open loop)

then re enable LTFTs and closed loop to dial in my part throttle LTFTs via LTFT % error? (reason i want to dial in the LTFTs with my NBs vs using the WB to 14.7 is that the two are not agreeing on whats 14.7 AFR. i trust the NBs to be more accurate at 14.7) When i use the WB to dial in part throttle AFRs to 14.7 in open loop, I am still getting positive LTFTs after re enabling closed loop.......

maybe i'm just not doing something right



some one please give me some better insight

[mirage2991]

I did the LTFT against MAF frequency, then use the paste % on the maf tables on my 05 vette and that gave me some great results. I'm right about -3 to -4. Can you do the same with the G8 or is that a completly differen animal? (I'm assuming you probably tired that and it didn't work that way for ya...)

[DSteck]

If you're going to run closed loop, you might as well tune the MAF using the narrow bands and long term fuel trims, because ultimately those are going to compensate for any discrepancies. Get LTFTs in the -2% to 0% range, and then do WOT using your wide band. If you use your wide band to do the part throttle stuff, you might end up with a +7% trim, so I don't see the harm in using the narrow bands for all the part throttle.

[boomer]

Thanks for the replies. tomorrow i will try to completely dial in my closed loop part throttle LTFT with my NBs first. then after they're all said and done, i'll work on the WOT portion of the MAF table in open loop with the wide band. does this sound like a better method?

I think my problem before was, i would get my WOT AFRs right where i wanted them by using my wide band, but because of my positive LTFTs, it was not consistent from day to day. so i need to get my LTFTs just in the negative %age.

[softy91]

I'm kind of jumping in the middle of this but assuming that the above is a given and there may be MAF drift---.

What about turning off the Lifts and run with the Sift to avoid drift from the MAF? I know that I have run into this over time.

[DSteck]

If you get your fuel trims into the negatives, then they won't carry into power enrichment (only positive trims will). This is why I think the part throttle MAF stuff should be done before doing wide open throttle tuning.

[RWTD]

If you get your fuel trims into the negatives, then they won't carry into power enrichment (only positive trims will). This is why I think the part throttle MAF stuff should be done before doing wide open throttle tuning.

You're exactly right, it should always be done 1st, IMO.

[EC_Tune]

X2 here. Part throttle and work your way up. No broken parts that way either.

[MyLS1Hauls]

What do you guys do about the "step" in the MAF table where you start making WOT adjustments to it. My LS2 appears to go into PE around 8000 Hz with my current settings and P1SC supercharger. It goes way rich when this happens...PE EQ is calling for 11.5, and its coming in around 10:1. So there will be a "step" in the MAF tables starting at 8000Hz, continuing to the end of the table. Is this a problem? It looks like it isn't possible to hit 8000 Hz at part throttle, closed loop, so I would think it should be fine.

[boomer]

What do you guys do about the "step" in the MAF table where you start making WOT adjustments to it. My LS2 appears to go into PE around 8000 Hz with my current settings and P1SC supercharger. It goes way rich when this happens...PE EQ is calling for 11.5, and its coming in around 10:1. So there will be a "step" in the MAF tables starting at 8000Hz, continuing to the end of the table. Is this a problem? It looks like it isn't possible to hit 8000 Hz at part throttle, closed loop, so I would think it should be fine.

great question. technically i'm going the same thing, but that "step" isn't really visually noticeable, but its there. i also only get my part throttle Hz up to about 7500 Hz and sometimes close to 8000 Hz.

Now that i have my fuel trims in line with my narrowbands in closed loop, everything seems to be more consistent at WOT.

[DSteck]

What do you guys do about the "step" in the MAF table where you start making WOT adjustments to it. My LS2 appears to go into PE around 8000 Hz with my current settings and P1SC supercharger. It goes way rich when this happens...PE EQ is calling for 11.5, and its coming in around 10:1. So there will be a "step" in the MAF tables starting at 8000Hz, continuing to the end of the table. Is this a problem? It looks like it isn't possible to hit 8000 Hz at part throttle, closed loop, so I would think it should be fine.

You might have a conflict between your PE table and another table. Poke around in the OL & CL tab.

[MyLS1Hauls]

You might have a conflict between your PE table and another table. Poke around in the OL & CL tab.

My issue with the large offset between commanded and actual A/F is due to the relocation of my MAF for the ProCharger setup. It was previously on a bend, right near a neckdown section in the stock intake. It is now in a straight section of 3.5" pipe. It is my belief that the MAF is now "seeing" more airflow than it was previously. I need to finish my part throttle MAF tuning first. Thanks for the input.