Excessive VE values?
03-06-2005, 07:26 AM
#1
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Excessive VE values? I copied this from my post on the HP Tuners site. I had alot of lookers buy no reply:
I have a '99 LS1 with AFR 205, comp 224/228 112 LSA cam and LS6 intake. I'm running 58 PSI of fuel. When I started with the stock calibration, I had 25% LTFT @ idle.
I have been tweaking the VE table, and its been helping, but at the rate I'm going, by the time I'm done, the 400, 800, 1200 and 1600 RPM column will be in the 90's! Is that to high, or should I start making more "global" changes like fuel control?
I have a '99 LS1 with AFR 205, comp 224/228 112 LSA cam and LS6 intake. I'm running 58 PSI of fuel. When I started with the stock calibration, I had 25% LTFT @ idle.
I have been tweaking the VE table, and its been helping, but at the rate I'm going, by the time I'm done, the 400, 800, 1200 and 1600 RPM column will be in the 90's! Is that to high, or should I start making more "global" changes like fuel control?
03-06-2005, 10:04 AM
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I think I might know the answer. After reading pages and pages of information off this great site, I've come to the conclusion its because I'm not disabling my MAF to tune. I think I have to disable the MAF to tune the VE table, then plug it back in and recalibrate the MAF to match the VE table. Is this correct?
03-06-2005, 11:04 AM
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Before you go nuts chasing air-side mixture "error" be
sure that it isn't really a mis-trimming from bad sensor
(best guess = O2s) action instead. Check this by a
wideband with closed loop enabled and disabled. If
the car idles / runs better in open loop than closed loop
then suspect the O2s are not or poorly lit.
sure that it isn't really a mis-trimming from bad sensor
(best guess = O2s) action instead. Check this by a
wideband with closed loop enabled and disabled. If
the car idles / runs better in open loop than closed loop
then suspect the O2s are not or poorly lit.
03-06-2005, 12:05 PM
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Good thinking, but these are brand new AC Delco sensors. I'll check to see if the heaters are working, then I'll start tuning w/ the MAF disabled.
03-06-2005, 02:12 PM
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there is absolutely no reason why your Ltrims are that far off only at idle, what do they look like at higher rpm where the sensors are not fooled by overlap? also look for an exhaust leak. I dont have problems in closed loop with cams until they hit the 240+ duration.