Nitrous Bottle Pressure logging

[Beer99C5]

Now that my fuel pressure is on the EGR PCM Pinouts (Thanks a Bunch TAQ!), that free's up the second input on my trusty Ol' V1.

Here are the Particulars of the sending unit for my Dynotune Nitrous Pressure
Nitrous pressure Sender Output = .005V per 100 psi
PSI Volt
0 2.547
100 2.552
200 2.557
300 2.562
400 2.567
500 2.572
600 2.577
700 2.582
800 2.587
900 2.592
1000 2.597
1100 2.602
1200 2.607
1300 2.612
1400 2.617
1500 2.622

This voltage is read from the black wire.

Little help making the PID for this?

[Ninety8C5]

Something like ((Voltage - 2.552)*20000) + 100, should work.

[Beer99C5]

Thanks that seems to work great (in Excel for various values), is there a way to force a 0 reading if the voltage 2.547 or slightly less (for when the bottle is not in?)

[Ninety8C5]

Oops, I missed the zero reading. I think that this is what you are looking for.

(({EXT.AD1} - 2.547) * 20000) = PSI

Sorry about that.

[Beer99C5]

No problem Appreciate the help

[Beer99C5]

So is this what I need for my User calc file? *CLC-00-002 being what I am adding on AD2 input?

# ================================================== ============================
# File details
# ------------
#
# This section defines various details about the file format.

*FILE

#Parameter Value Description
#---------- ---------------- ---------------------------------------------------
VERSION 7.1.1 File version
DECSEP . Decimal separator used in this file



# ================================================== ============================
# Units
# -------------------
# See sae_generic.txt for more information on the *UNITS section

*UNITS

#Code System Abbr Description
#-------- ---------- -------- --------------------------------------------------
PSI Imperial PSI "Pounds Per Square Inch"
# ================================================== ============================
# Add slot definitions here
# --------------------------------
#Units Low High Fmt Expression
#------------ ------------- ------------- ---- ---------------------------------
*CLC-00-001
PSI 0.00 100.00 .2 "({GM.EGRS}*25)-12.5"
# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
#Code PRN SLOT Units System Description
#------------- ---- ------------ ------------ ------------ ---------------------
CALC.FP F001 CLC-00-001 PSI Fuel "Fuel Pressure"


*CLC-00-002
PSI 0 1500 1 "(({EXT.AD2}-2.547)*20000)"
# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
#Code PRN SLOT Units System Description
#------------- ---- ------------ ------------ ------------ ---------------------
CALC.NP F002 CLC-00-002 PSI Accessories "Nitrous Main Line Pressure"

[Ninety8C5]

That should do it. I think you can leave out the first '(' and the last ')', but it shouldn't bother anything. I left them there from the first equation.

I like the color of your car. I have a 98 Nassau Blue coupe.

[joecar]

Beer,

I took the liberty to "optmize" your calc_pids... see attached...

(psi units are already pre-defined)

Cheers
Joe

[Blacky]

FlashScan A/D inputs are accurate to +/- 0.01V, so measuring down to 0.005 Volts will not be 100% accurate.

The PSI displayed by EFILive will be accurate to +/- 200PSI

And to get it to display 0 under 2.547V, you could do this:
(oh and I changed the precision to 0).

psi    0    1500    0    "Iff({EXT.AD2}<2.547,0,({EXT.AD2}-2.547)*20000)"

Regards
Paul

Now that my fuel pressure is on the EGR PCM Pinouts (Thanks a Bunch TAQ!), that free's up the second input on my trusty Ol' V1.

Here are the Particulars of the sending unit for my Dynotune Nitrous Pressure
Nitrous pressure Sender Output = .005V per 100 psi
PSI Volt
0 2.547
100 2.552
200 2.557
300 2.562
400 2.567
500 2.572
600 2.577
700 2.582
800 2.587
900 2.592
1000 2.597
1100 2.602
1200 2.607
1300 2.612
1400 2.617
1500 2.622

This voltage is read from the black wire.

Little help making the PID for this?

[Beer99C5]

Thanks all, not sure if 200 +or - is worth the effort now, I will try it though (its only one wire 2' long). Both V1 and V2 have the same A/D inputs accurate to +/- 0.01V?