voltage offset question
My equation reads : volts/.6266 + 10.32 (.6266 because lc-1 will only let me set a max afr of 17.98?)
I realize you have to create a custom pid, I just don't know exactly how/where to place this equation to get the desired results.
Can someone show me the way??
0V=10
5V=20
AFR=v*2+10 is the formula and should allready be predefined in the software for one if the other Widebands
or do 1V=10AFR
and 2V=20AFR
this is what i use for my lm-1 settings and they should work the same for the lc-1
When I go to programthe AFR range of 10-18 when I return to the programming screen it read 10-17.98.I don't know why.
I doesn't really matter why....as long as I use the correct #'s in my equation it shouldn't matter.
I need to know how to set up a custom pid using my offset equation so that HPT reads the same AFR as logworks.
I have been ideling in the driveway for quite some time and I think my nieghbours are getting pissed..
consistent and the gain error can be nonlinear as
well. I don't think correcting it this way is reliable.
Try acquiring a series of straight voltage measurements
with the LC-1 set to output flat (10:1 = 1.000, 18:1 =
1.000; 0.0, 2.0, 3.0, 4.0, 5.0 in turn). Get the true
voltage output measured without the scanner hooked
to the LC-1, get the true voltage with them hooked up
(talking DMM here, an tie-breaker). And get the scanner
logged value. Also handy would be a reading of ground-
ground voltage (DMM) with the two not connected.
Now do it again a few days later in different weather
(changing the heater power profile).
One guy did this (one session only), I saw the data
and it was just plain bent. Not a straight line to be
found. So making a straight line fit for it, is not going
to make it correct. If your situation is anything like.
The gain error is really perplexing and I would like to
know which end it's on, the output of the LC-1 or the
input of the logger pod. Guess if I weren't so lazy I'd
try that out myself. But I have a different wideband.
I was reading about the offsets over on HP's forum and the formula used there was :Wideband reports 3.0v
EIO reports 2.7v
so you have an offset of .3 volts (WB-EIO)(3.0-2.7)
You will need to make a Custom PID for the EIO to be accurate
volts / (voltage range/Device range) + (Minimum value of device range)
Volts/ (5/8) + 10
5/8= .625
Volts/ .625 + 10+offset in value of device\
Edit: fixed this part of the equation below
.3/.625 =0.48
so in our example
Volts / .625 + 10.48
Thats what I am trying to do however I don't know where to use this formula.
Do I still log raw voltage ( sens .50) and use this formula to spit out an AFR reading??
My car will be off the road in a couple of weeks and I have yet to do any tuning.
Should I move the grounds around to try and get rid of the offset?
Should I ditch the LC-1 and get another WB that doesn't have this problem??
Should I get a yugo???
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I was reading about the offsets over on HP's forum and the formula used there was :Wideband reports 3.0v
EIO reports 2.7v
so you have an offset of .3 volts (WB-EIO)(3.0-2.7)
You will need to make a Custom PID for the EIO to be accurate
volts / (voltage range/Device range) + (Minimum value of device range)
Volts/ (5/8) + 10
5/8= .625
Volts/ .625 + 10+offset in value of device\
Edit: fixed this part of the equation below
.3/.625 =0.48
so in our example
Volts / .625 + 10.48
Thats what I am trying to do however I don't know where to use this formula.
Do I still log raw voltage ( sens .50) and use this formula to spit out an AFR reading??
My car will be off the road in a couple of weeks and I have yet to do any tuning.

To answer your question using the .3V offset you noticed...
You said you saw 2.7 on the EIO and 3.0 was commanded on the LC1. Assuming this was true for the range you'll be recording in, then your new equation would be ((Volts+.3)*3)+7.35. This will correct the .3V offset and keep the stock LC1 range of 0V=7.35AFR and 5V=22.35AFR.
Once you figure out the right equation, you need to create a custom PID. Try searching here or over at the HPT forums on how to create custom PIDs. I use EFI Live, so my process is different.
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