Adjusting LTFTs?
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7th Gear
Joined: Mar 2007
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Adjusting LTFTs?
Mike advised me to adjust LTFTs and adjust them as close to zero as possible. How is this done? I am running about 10% at 60 mph 5% when going up hill and 15% going down. Do I adjust ignition, injector or fuel. All is set at Diablo tune except 2% advance at all 3 rpm levels.
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Actually, I set mine to a small negative number. That way the PCM sees the car running "rich" and it doesn't splash in gas for WOT runs. With the "splash" in check, then what I have set for A/F during WOT is set to the actual A/F I target. A positive number of any kind will have extra gas tossed into WOT and trying to get a "set" WOT A/F is a nightmare. There are a few other things to consider but I do most of the LTFT settings with a tweak of the MAF table. The % is read as the TPS goes to WOT. I look at the steady state cruise on level ground to see the LTFT and that is the % I work.
That information is what I use for my FI application in the LS6 in my Camaro. An engine is an engine and I imagine the function is the same for the LS2.
Is that (WOT) why you are working on the LTFTs? If not, why waste your time? THE PCM does all the math on this.
Elmer
That information is what I use for my FI application in the LS6 in my Camaro. An engine is an engine and I imagine the function is the same for the LS2.
Is that (WOT) why you are working on the LTFTs? If not, why waste your time? THE PCM does all the math on this.
Elmer
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7th Gear
Joined: Mar 2007
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Got it done!
I decreased injector slope by 6 this got me to just above 0 most of the time. True the ECU adjusts but not enough to compensate for LT headers & Corsa exhast, SLP intake. The next test will be at the track.
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Joined: Jun 2001
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Well hell... You didn't mention any of that stuff in the question!
