OMNI 3-bar MAP sensor scalings
Oct 3, 2013, 08:57 PM
#17
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I know this tread is old but i cant find that map scaling map in my TephraMod V7 rom
do i have to add it ?? i just ordered omni 3bar map sensor and i dont know what to do next
pls help guys
thnks a lot
do i have to add it ?? i just ordered omni 3bar map sensor and i dont know what to do next
pls help guys
thnks a lot
Oct 4, 2013, 06:11 AM
#18
You may have to add the table defs to your xml. You should be able to find them here:
https://www.evolutionm.net/forums/ec...tructions.html
https://www.evolutionm.net/forums/ec...tructions.html
Aug 2, 2015, 09:42 AM
#27
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1)
Why is this scaling not quite linear? How come it isn't:
24 (vs. 25)
48 (vs. 49)
72 (vs. 70)
96
120
144
168 (vs. 170)
192 (vs. 195)
2)
For EvoScan logging, I am adding a new item with that formula. I noticed there is already an Omni 4Bar item in my Tephra v7 XML, and it has a slightly different formula than yours (aside from the 4bar scale).
From this post, the 3Bar formula is: * x + 0.161 - y
In the Tephra XML, the 4Bar is: * x - y
What is the purpose of adding 0.161 to x for the 3bar sensor, and/or why does the 4bar item in Tephra XML not add 0.161?
Thanks!
Last edited by jsmcpn; Aug 2, 2015 at 10:04 AM.
Aug 2, 2015, 06:06 PM
#28
Two questions:
1)
Why is this scaling not quite linear? How come it isn't:
24 (vs. 25)
48 (vs. 49)
72 (vs. 70)
96
120
144
168 (vs. 170)
192 (vs. 195)
2)
For EvoScan logging, I am adding a new item with that formula. I noticed there is already an Omni 4Bar item in my Tephra v7 XML, and it has a slightly different formula than yours (aside from the 4bar scale).
From this post, the 3Bar formula is: * x + 0.161 - y
In the Tephra XML, the 4Bar is: * x - y
What is the purpose of adding 0.161 to x for the 3bar sensor, and/or why does the 4bar item in Tephra XML not add 0.161?
Thanks!
1)
Why is this scaling not quite linear? How come it isn't:
24 (vs. 25)
48 (vs. 49)
72 (vs. 70)
96
120
144
168 (vs. 170)
192 (vs. 195)
2)
For EvoScan logging, I am adding a new item with that formula. I noticed there is already an Omni 4Bar item in my Tephra v7 XML, and it has a slightly different formula than yours (aside from the 4bar scale).
From this post, the 3Bar formula is: * x + 0.161 - y
In the Tephra XML, the 4Bar is: * x - y
What is the purpose of adding 0.161 to x for the 3bar sensor, and/or why does the 4bar item in Tephra XML not add 0.161?
Thanks!
Concerning 2), I just wrote it like that to make it easier to start at what should be your local atmoshperic pressure and adjust from there. I could have written this instead, which leads to the same formula but is a bit more complicated to explain:
And here is the correct Evoscan equation: 0.17886 * x + y
where y = 0.161 - your local atmospheric pressure (14.7 at sea level)
where y = 0.161 - your local atmospheric pressure (14.7 at sea level)
Aug 3, 2015, 01:29 PM
#30
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Regarding 1), frankly I don't know. I don't even remember how I got to the scaling I have now. I can check the logged values for my 3bar compared to my zeitronix sensor's reading to see if they match up perfectly, but I imagine I would have done that as well when I settled on those scalings. I suspect that changing them for the linear values you propose wouldn't change the logged value very much since they seem to be pretty close.
Concerning 2), I just wrote it like that to make it easier to start at what should be your local atmoshperic pressure and adjust from there. I could have written this instead, which leads to the same formula but is a bit more complicated to explain:
Concerning 2), I just wrote it like that to make it easier to start at what should be your local atmoshperic pressure and adjust from there. I could have written this instead, which leads to the same formula but is a bit more complicated to explain:
I bought this sensor to use with the Grimspeed boost controller, FWIW, but I don't want to even try MAP-based boost control until the Omni 3bar is calibrated properly.
Last edited by jsmcpn; Aug 3, 2015 at 01:33 PM.