PE table Excessive?
Starting to wrap my head around PE table and its functions and as I look at my tune, it seems to be excessively on the rich side. see below:
1.4853515625 1.4853515625 1.4853515625 1.4853515625 1.4853515625 1.4853515625 1.4853515625 1.4853515625 1.4853515625 1.443359375 1.416015625 1.375 1.375 1.375 1.375 1.333984375 1.333984375 1.333984375 1.333984375
The story behind the car is that it was dyne tuned by Hawk's performance in 2009 as an A4 stalled car. Dyno tune happened at the same time heads and cam went in. I switched to an M6 and the car hasn't been driven much due to various reasons, but I'm back in it now. My work in progress tune is copied below.
I have a Wideband installed now so I can go log some data, but I have a Racetronix pump/hotwire kit and 36lb injectors ready to go in first. I know I'm at or beyond the limit of stock fuel, just haven't had a chance to put them in yet. I suspect that any logging I do will be skewed by fuel system not being able to keep up. Even so, when I compare my PE table to the files available in the repository, they seem really rich. 14.72/1.485=9.9AFR.
Am I missing something? im getting started with MAF then VE tuning once the new fuel system is in, but I think my PE table has a lot left to give before I even get moving.
I would not change it yet. PE is just a multiplier.
Leave as is, do a wot pull, see where rear AFR is and compare to commanded AFR.
My concern to a drastic change is that if you have this 1.4xx factor and it barely keeps 13.2 AFR at wot (just and example) changing to 1.2x or lower) may put you critically lean.
Until you can compare/validate vs a real wideband reading, you don’t have a point of reference.
I would not change it yet. PE is just a multiplier.
Leave as is, do a wot pull, see where rear AFR is and compare to commanded AFR.
My concern to a drastic change is that if you have this 1.4xx factor and it barely keeps 13.2 AFR at wot (just and example) changing to 1.2x or lower) may put you critically lean.
Until you can compare/validate vs a real wideband reading, you don’t have a point of reference.
Ive logged a few pulls while scanning and had to get off the throttle quicker than I wanted to, but even when limited by traffic and road conditions, short WOT stints put me up over 93% IDC. Im not going to worry too much about gathering data now when there's no way for my fuel system to keep up.
Ive got the pump and injectors on my workbench, I just have to find an afternoon to do it. The tank is full from winter storage so I wanted to drain it down a bit before I dropped the tank.
Ive logged a few pulls while scanning and had to get off the throttle quicker than I wanted to, but even when limited by traffic and road conditions, short WOT stints put me up over 93% IDC. Im not going to worry too much about gathering data now when there's no way for my fuel system to keep up.
Ive got the pump and injectors on my workbench, I just have to find an afternoon to do it. The tank is full from winter storage so I wanted to drain it down a bit before I dropped the tank.
If your fuel system can't keep up with the fueling, then commanded really won't matter. You could command 1:1 or something crazy but your injectors won't be able to do it. As stated above, the duty cycle may come down when you AFR is actually correct. If you are actually like 9:1 then that's pig rich and you can lean that up a lot. It will make more power too, so worth checking into.
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If your fuel system can't keep up with the fueling, then commanded really won't matter. You could command 1:1 or something crazy but your injectors won't be able to do it. As stated above, the duty cycle may come down when you AFR is actually correct. If you are actually like 9:1 then that's pig rich and you can lean that up a lot. It will make more power too, so worth checking into.
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if I were you, I would get that WB going, set your targets to 12.5 in PE (1.17) and slowly work up to WOT watching your AFR closely. Then tune the airmass models as applicable the usual way.
Some, maybe a lot, of Tuners simply adjust the PE to get what they desire for AFR out the tailpipe at WOT.
It works, but the tune isn’t calibrated.
I don’t tune that way. I prefer the proper way as taught by Banish years ago. In other words a calibrated tune.











