could someone please explain to me exactly what barometric learning does on my 2007 dodge ram 5.7 hemi with a NGC-4 PCM. Thanks
barometric learning 2007 dodge ngc-4
could someone please explain to me exactly what barometric learning does on my 2007 dodge ram 5.7 hemi with a NGC-4 PCM. Thanks
It updates the Barometric pressure reading, which is critical to its fuel calcs.
Its purpose is to keep the engine running a bit better just in case you drive straight off the beach to the top of a 5000ft mountain without ever shutting off the engine.
When you add Boost, it MUST be disabled.
you realize the difference in Baro between Philly(39ft elv ) Denver(5280elv) is .005 Bars on an average day.Originally Posted by duster360
today(5.12.24)in Denver@ 8am it's 30.27(1039Millibars, 14.87psi ) and 29.87(1011Millibars, 14.67psi) in Philly, At Mount Davis in PA (3213elv) it's 29.67(1005millibars ,14.57psi.....so
No it's not what barometric learning does.
to answer the question, (Dave is partially correct, it is used in fuel calc)
1st understand that IAT,MAP, o2 sensors take other readings also,
the ECU takes LOCAL Barometric reading (actually in Millibars) and compares it to an average MAP(in Millibars) value taken from W.O.T events and uses it as a "standard" ....the ECU doesn't care where you are or what the outside baro value is , just what the difference is between outside Baro(measured at the IAT sensor) and Manifold Air Pressure ,
In operation at or above Throttle Delta(Table 44267)the ECU uses actual current MAP reading in fuel calculations, below Throttle Delta it uses the stored "standard" Value, reason being is fluctuations, reversion and inconsistent air density are more prevalent have a greater +/- swing during part throttle acceleration(check the attachments)
In theory Map + Manifold vacuum should equal Atmosphere pressure(Baro) , but reality is we have a few things that keep that from happing.....look at the Attachment L1 it's a 30sec screen grab, in the White circle this 04 ram stock expect K&N cold air intake. is at Idle & a little dry hop to clean the tires, the Yellow Line is a math parameter, Manifold Vacuum mins the combined value of Baro-MAP, at Idle the Yellow line is very erratic ups & downs, now the Next attachment is same log capture of a 0ish to 60ish romp, the yellow line is not perfect but has less dips and No bumps in-till gear shift. ,last attachment is the same truck (same log) pulling away from a traffic light, there is a yellow reference added(line = 0)...Notice it's ALL over the place....
Point is , instead of constantly needing to readjust base point for fuel calculations it uses pre stored average.
Now some real world results, in the last 10 years I've bought, sold, and worked on over 100 3rd gen rams, I currently own 20 , three are track only trailer queens, one is a low 11 daily(ish)driver another one is amid 12 ish daily and the another 8 used somewhat on a weekly basis(yes Insurance is a F'N b!tch)
Every truck(or Hemi car) I've had, I get base line Logs roughly 40 hours worth, every time I compare Fuel Millage between Baro Leaning enabled and disabled , Enable is Always 2 MPG average better.
04 RAMGTX........ 8.91@151mph 392Ci G3Hemi 3600lbs 2.6HP/Ci Naturally Aspirated
05 RAMGTxtreme 9:45@142mph 426Ci G3Hemi 4000lbs 2.2HP/Ci Naturally Aspirated
09 Challenger Drag Pak 8.88@150mph 376Ci G3hemi 3650lbs 2.6HP/Ci Naturally Aspirated
G3 Hemi Videos
https://www.youtube.com/channel/UClS...5mXdDR5sOxs10Q
If in doubt, multiply everything by 1.1.
And that has nothing to do with the question, or any of the answers.
Gonzo= 14 Ram 4x2 441Ci 9:90s on pump 93
Lazy boy= 12 Ram 4x2 362Ci 11:80s on pump 93
The Bee= 04 Rumble Bee 4x2 370ci 10:60s on pump 93
Maybe this will help.
https://forecast.weather.gov/product...t=OSO&site=bou
Seems like a drag racer would understand the effects of DA, but maybe not?
If in doubt, multiply everything by 1.1.
LOL...i love it when the ignorant are so arrogant when shouting their ignorance for all to hear.
You realize the difference in Barometer readings used for weathermen are not actual Absolute Pressure read by a MAP sensor? Obviously not..... lol
Here read this: https://www.weather.gov/bou/pressure_definitions
Meteorologist use "MEAN SEA LEVEL PRESSURE" . Your stated Barometer values are normalized for local Altitude so the simple minded(??) don't get too confused.
All experienced tuners know that a 5300ft altitude is typically around 85kPa or about 12psi.
I've tuned cars in Mexico City, Mexico where Baro is in the mid to high 70s ~10psi
So when your Baro goes from reading 101kpa in San Diego and then go skiing at Snow Summit(7200ft) the BARO as measured by your car's MAP sensor would be off BY over 2psi, if Baro learning wasn't working.
That would mean WOT Pressure Ratio would be go from 1.0 on the Beach to .8 on the Mountain without Baro Learning. For that heap of shit 20 year old Ram in question, that would mean the VE is off 2 Rows and NONE of Baro Corrections are doing their job.
All factory Boost cars, Hellcats, Srt-4, take and actual Baro reading. NA cars, use "WOT" to readjust Baro.
Last edited by duster360; 3 Days Ago at 05:19 PM.
Yes is certainly does. @spoolboy just correcting the misinformed.
Last edited by duster360; 3 Days Ago at 04:26 PM.
Well Speaking of ignorant, No need to insult the original poster's ram for asking what Baro learning does on his ram with an NGC4 ECU, Not a Hellcat , Not an SRT 4 , Not sensed map, Not VE modifiers, I understand what DA is, and if you two ignorant phucks think any of this has to do with what Baro leaning does on one of these , no wonder I've fixed a few of Dave Trojan and Dennis Dosa (I know I didn't get that right, I do sincerely apologize for the misspelling ) tunes over the last few years.
you both can keep on being "also rans"
LoL , and I use to wonder why people laugh at you Dave.
Gonzo= 14 Ram 4x2 441Ci 9:90s on pump 93
Lazy boy= 12 Ram 4x2 362Ci 11:80s on pump 93
The Bee= 04 Rumble Bee 4x2 370ci 10:60s on pump 93
If in doubt, multiply everything by 1.1.
Lot of angst in here. Nobody's got it quite right though... Who wants to hear about this feature from a former Chrysler engineer who has actually been balls deep with these algorithms?
Not me. Not me
I do not
Check out old Addy
https://youtu.be/9tJri3uuVf0?si=OjnvzZIm0olp88bf
She knows about station pressure and how low the avg in Denver is : )
Last edited by LilSick; 2 Days Ago at 03:43 PM.
Not me either. I've worked with enough engineers to know they're usually full of shit or incapable of grasping reality outside of a computer model. If you were going to inform us, you would have.
If there's one thing engineers love, it's telling everybody how smart they are.
Damn, figured you'd give me a little more credit than that lol. Might as well have fun with it while I'm at it right..
No one knows you or cares....but that's not a shock as you're just another rando with an inferiority complex just spouting off in hopes for a shred of recognition but as typical of your kind, offering nothing, contributing nothing and never having anything worthwhile to share.
I've seen carnage after my tunes get "fixed" by some no-name, tard. Sure thing rando...lol
Last edited by duster360; 1 Day Ago at 02:17 PM.
Go for it.
Besides what I already said, I'd should have added Throttle Airflow since its DBW
He won't. He's full of shit.
If in doubt, multiply everything by 1.1.
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