Idle setup with specific Scalars names

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Idle setup with specific Scalars names

Unread postby 89FiveOh » Thu Feb 08, 2018 6:43 pm

Hello,
Can someone explain the goal in setting the idle and what specific scalars are necessary to get a perfect idle. I have read and read and read again the idle air 101 and Im still missing something. My procedure has been:
Yank the spout
Disconnect IAC
Disconnect TPS
then I try to get the idle that I want which seems to be 848 rpm. Afterwards, I datalog a warm idle and determine TB airflow and air thru the IAC based off the duty cycle. My average has been 1.275 lb/min total airflow. Based on a ~35% duty cycle, my TB flows 1.101 which leaves 0.174 flowing thru the IAC.

Is there a scalar that reflects total airflow?
ITHAMBA should be 1.101 im guessing.
I input the ISC xfer at 848 with .174 ISC flow at Idle Neutral Air.
Is there a scalar for the amount of air flowing thru the IAC at idle?

My problem, with it being warm, runs like a champ. I save my tune, restart it and idles fine. However, the next day on a cold start, it wont idle for crap and wont hold idle till it gets warm.
Log the cold start and the duty cycle is pegged at 54% and I have never been able to keep IPSIRB at zero. Its always .4.

What am I missing? After warm idle scalars is set, should I be tuning elsewhere to combat the cold start even though I have a pretty consistant warm idle with the calculated scalars mentioned above?

Thanks

Please list the required scalars used for dialing in idle air if possible.
89FiveOh
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Re: Idle setup with specific Scalars names

Unread postby decipha » Thu Feb 08, 2018 7:00 pm

if your using the a9l2 tune or a tune with the 'mechanical idle' all you have to do is adjust the throttle stop so IPSIBR is as close to 0 as you can get it at warm operating temp

if your using henry's actual method of controlling idle then you will have to do quite a bit of work.

if you have 1.275 lb/min of total airflow at idle and your isc unplugged then the iac contribution is 0 since its not giving you any airflow

that would mean ithbma the airflow through the throttle body and fn875 the idle airmass function would have the same value

x - x == 0 offset

problem with that is that the iscdc minimum value os 10% to be closed which still moves a touch of air so it will raise the idle a cunt hair but spark will drop to compensate to make up the difference no big deal

now just dial in the isc multiplier table fn1862 to dial in the air needed for cold starts, all the details are in the startup write up

https://www.efidynotuning.com/startup.htm
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Re: Idle setup with specific Scalars names

Unread postby 89FiveOh » Thu Feb 08, 2018 8:08 pm

Thanks .
I failed to mention after I set it at lowest possible idle possible without conkin out and er’thing unplugged ~760, I then enter my new nubase and then datalog with everything connected minus the spout and adjust my tb setscrew until I hover around 35% duty cycle. It is after I achieve the 35% duty cucle, I then calculate the above mentioned scalars.

I would assume my way of skinning this cat is the real problem.. Lol

So your suggestion after idle air scalars are calculated, fix the cold start in the xfer?
I would assume the goal here would be increase something in the table?
89FiveOh
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Posts: 41
Joined: Thu Jan 11, 2018 5:13 pm
Name: Andy Borden
Vehicle Information: 1989 Mustang GT
GUFB A9L
Binary Editor/EEC Anaylyzer
Innovate MTX-L PLUS
MOATES QuarterHorse
308
Custom Cam (HR)
AFR 165, 58cc
BBK 75mm (24lb/hr calibration) MAF
5 speed
3.73 gears
NA
Full length BBK headers with H-pipe thru Flowmaster mufflers

Re: Idle setup with specific Scalars names

Unread postby decipha » Thu Feb 08, 2018 8:18 pm

the isc multiplier table is the percentage of air needed to maintain idle for a non stabilized engine, simply kick up the multiplier in realtime until it gets ipsibr near 0 during warm up
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90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
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98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce

Re: Idle setup with specific Scalars names

Unread postby 89FiveOh » Thu Feb 08, 2018 9:45 pm

Thanks once again.
One last question, would IFAM be relevant to the total air at idle in which the tb and iac air is calculated?
ITHBMA + DEBYCP = IFAM
89FiveOh
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Posts: 41
Joined: Thu Jan 11, 2018 5:13 pm
Name: Andy Borden
Vehicle Information: 1989 Mustang GT
GUFB A9L
Binary Editor/EEC Anaylyzer
Innovate MTX-L PLUS
MOATES QuarterHorse
308
Custom Cam (HR)
AFR 165, 58cc
BBK 75mm (24lb/hr calibration) MAF
5 speed
3.73 gears
NA
Full length BBK headers with H-pipe thru Flowmaster mufflers

Re: Idle setup with specific Scalars names

Unread postby decipha » Fri Feb 09, 2018 6:00 am

no
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91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce


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