This Tune RUNS LEAN...RIGHT!?
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From: Rutherford, NJ
This Tune RUNS LEAN...RIGHT!?
Ok, i'm a bit confused on the power enrich table vs. rpm...I was looking at a GM Stage 2 tune....and to me, it seems like it's running WAY LEAN under WOT. Maybe i'm reading it wrong, but to me, at 6750 rpm, it seems like it's commanding a 13.15 af ratio! Am I right? The stoich is set at stock which is 14.69971...here's a pic:
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From: Nashville
You are reading it correctly. However, it doesn't look TOO bad. You can see they have a 12.5-1 ratio right in the power band, and then lean out as you get out of the power band. Its a misconception that you need a totally flat AFR across the entire RPM range. You could probably richen that up a bit with little loss of top end power.
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From: Rutherford, NJ
Originally Posted by Blown 4-banger
Dude if you were running a 13.5 commanded afr then your actually AFR had to be around 14:1!!!one!!!!11111!!!111!11!1111!!111111!1!1!one! one111one1!!
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From: South Carolina
Originally Posted by denny
I personaly get no knock with this bin. Do you get any knock? I remember you used to be the king of knock...and you where like this
but i think your right it is running lean....especialy me running more air (2.8") then what the stage II was meant for a 3".
a little chart for the commanding AFR
1.30 = ~11.3
1.29 = ~11.4
1.28 = ~11.5
1.27 = ~11.6
1.26 = ~11.7
1.25 = ~11.8
1.24 = 11.9
1.23 12.0
1.22 12.1
1.21 12.2
1.20 12.3
1.19 12.4
1.18 12.5
1.17 12.6
1.16 12.7
1.15 12.8
1.14 12.9
1.13 13.0
1.12 13.1
1.11 13.2
1.10 13.3
1.09 13.4
1.08 13.5
but i think your right it is running lean....especialy me running more air (2.8") then what the stage II was meant for a 3".a little chart for the commanding AFR
1.30 = ~11.3
1.29 = ~11.4
1.28 = ~11.5
1.27 = ~11.6
1.26 = ~11.7
1.25 = ~11.8
1.24 = 11.9
1.23 12.0
1.22 12.1
1.21 12.2
1.20 12.3
1.19 12.4
1.18 12.5
1.17 12.6
1.16 12.7
1.15 12.8
1.14 12.9
1.13 13.0
1.12 13.1
1.11 13.2
1.10 13.3
1.09 13.4
1.08 13.5
thanks for posting that i was looking at that chart and i didnt know how to read it i was like
maybe i shouldnt order hp tuners if i cant even understand this but nevermind
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From: Pittsburgh, PA
Its only lean if other enrichment modes such as Cat Over Temp and Piston Protection are disabled. Power Enrcihment isn't the only enrichment commanded A/F is calculated from. Setup a PID to log Commanded A/F to see the real tune.
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From: Rutherford, NJ
Well....they are definately not running lean...the other tables under fueling...welll all affect a/f ratio as well. So, even though it was commanding a 13...it still could've been safe...I just made his car extra safe. But i'm pretty sure GM knows what they are doing...and the gm stage 2 guys that dynoed are all rich as hell...its just the tune is a little awkward to look at (to me at least), but I can't see GM actually making the car run a 13...
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From: South Carolina
yeah and whats my car gonna be running like if i have stage 2 with a header and downpipe does the header and dp make you run even leaner on top of an already lean stage 2 because that is definatly no good.
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From: Rutherford, NJ
....I belive every gm stage 2 dyno i've seen has a/f ratios in the 11's....I just changed this one because it wasn't working right....Remember, every car is different....
wow it's 330 in the a.m. and i have work in ..(yes Christmas eve).. 3 in ahalf hours...I think i'm going to bed now lol
wow it's 330 in the a.m. and i have work in ..(yes Christmas eve).. 3 in ahalf hours...I think i'm going to bed now lol
**** my pe table was much richer than that, still is too even with my modified stg II on my car...
sorry I missed your call friday night adam, I was at a christmas party and a little too drunk to talk..
sorry I missed your call friday night adam, I was at a christmas party and a little too drunk to talk..
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From: Rutherford, NJ
lol that's quite ok...I just needed and still need to ask you a question about the conifuration....i'm a bit confused...but maybe later because i'm one lazy **** right now lol and I don't feel like typing, talking, moving as of right now
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From: Ft. Benning, GA
MY PE table starts ar around 1.24 and ends up around 1.10 - 1.09 around 6k-7k here with dense air and a 2.6, remember your results may vary and the best thing to do is put a wideband on your car and tune accordingly.
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