Dfco Help
02-15-2008, 07:33 PM
#1
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Dfco Help
Ive been trying to mess with tuning dfco with my cam. I ran a log originally and looked at where the map values were when I let off the gas. So I thought I had that figured out. Funny thing is, the original tune had the dfco enabling before 5% tps. On my truck, which has DBW, 13% is my foot completely off the gas. so I changed that too.
The problem is that its not aggressive enough. I want it to come on sooner and then when it does shut off, the whole truck jerks back on.
I also don't understand what the BARO variable is or where its read from.
Any help or general pointers about the dfco settings would be very helpful.
Thanks
My log is attached
The problem is that its not aggressive enough. I want it to come on sooner and then when it does shut off, the whole truck jerks back on.
I also don't understand what the BARO variable is or where its read from.
Any help or general pointers about the dfco settings would be very helpful.
Thanks
My log is attached
02-15-2008, 08:36 PM
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I have mine working just how I want it after my cam swap. I actually had it too aggressive at first and had to back it off because it came on too early. Here is a tune with my current settings and a log of it working. Also don't get too caught up on the TPS settings with the DBW I thing there must me some extra math going on there. I upped my settings a little in that area by not near as much as the logs suggested that it should be. I also reduced the "Throttle Cracker" table by 75%
02-15-2008, 10:32 PM
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I am only posting this comment to see if dc_justin is paying attention.
Go into the minimum inj setting, bottom the whole table out to where you injs are at minimum and turn off dfco. TA-DA, lean decel. Oh yeh, you'll need to delete th pulse adder table and maybe reduce the offset table as well. I am in lean decel EVERYWHERE. LMAO (seriously though for me)
Go into the minimum inj setting, bottom the whole table out to where you injs are at minimum and turn off dfco. TA-DA, lean decel. Oh yeh, you'll need to delete th pulse adder table and maybe reduce the offset table as well. I am in lean decel EVERYWHERE. LMAO (seriously though for me)
02-15-2008, 11:38 PM
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I logged map and barometric pressure to find out what map my truck runs at during idle and cruise. I only raised the enable map about 3 kpa because my map drops plenty low enough on decel to enable DFCO. I raised the exit map to about 10 kpa below the map that my truck idles at. I multiplied the TPS table by 1.5 for the increased TPS position with the cam and I decreased the Throttle Cracker table by 75% because I believe that helps the throttle close faster when you lift off and in turn allows you to get into DFCO faster. You should also check the Enable TPS settings to make sure they are low enough to be under your normal cruise RPM. One last thing I did to help get into DFCO faster was to increase the Blending table 1.5 times. This pulls timing faster on decel which allows DFCO to kick in a little earlier. I am very happy with how these setting have been working for the past few days. The DFCO kicks in at just the right time when I let off the gas and I don't have any transition problems when coming to a stop or getting back on the gas.
02-16-2008, 11:59 AM
#10
1. What happens when it comes on too early? 2. And to repeat exhappen, can anybody explain the barometric vs. map table? I don't understand how you can measure the barometric pressure if your only sensor is the MAP. Doesn't barometric pressure mean the actual atmospheric pressure outside of the engine? And how could it change much from 103?