Just curious does anyone know how Cranking VE actually functions?

[verlon]

If I wanted to make my car start a little easier as in less aggressive than factory so I won't disturb my neighbors firing it up at 5:00 a.m. is cranking VE the way to do it?

No.
You need Startup Airflow - [ECM] 12194 and Startup Idle Flare Control - [ECM] 12643
[ECM] 12194 has wrong scaling, it is actually twice bigger.

[daktah]

thanks, i managed to completely miss that airflow table somehow. that table plus startup time over/underspeed right next to it should be exactly what i need for what i want to do

[morepowerjoe]

thanks, i managed to completely miss that airflow table somehow. that table plus startup time over/underspeed right next to it should be exactly what i need for what i want to do

Let us know how you adjust this and what it actually does. I am very interested.

[daktah]

Let us know how you adjust this and what it actually does. I am very interested.

cutting only the airflow table didnt do the trick on its own, i also had to mess with the maf steady state values as the engine would still continue to high idle with the ecu keeping timing low to keep it under control (lots of fuel + low/negative timing = loud). this is exactly what i ended up doing:

engine > idle > airflow: startup

startup time overspeed and underspeed
-40 to 25: 1 second
(being less aggressive with cuts below freezing for starting reliability (on all tables))
46 to 306: 0 second
(makes the ecu drop out of the startup airflow table immediately once the engine fires, i believe)

startup airflow
-40 to 25: stock
46 to 306: -50% all cells

maf s/s startup
-40 to 25: stock
46 to 306: -50%

maf s/s stepdown
stock

maf s/s stepdown delay
1 second
(lets it kick the engine for starting reliability but nearly immediately drop out of steady state so it can low idle)

engine > spark > advance: catalyst heating

normal, coast, idle p/n, idle gear
copied values from high octane table for same airmass x spark values, interpolated between columns where required
(i have long tubes with high flows so accelerated lightoff is pointless, plus it tends to lope due to low timing which is loud)

st ect mult, ect mult, ert mult, tps mult
0 all cells
(probably makes the above pointless but whatever)

engine > spark > advance: startup

cranking
-5 degrees all cells
(mostly trying to fix a random hot start knock, seems to have worked, likely can be left stock otherwise)

startup flare cont
stock

mult
stock

with all of that now it just flares up to about 1500 rpm then pretty much immediately once the needle hits 1500 it drops back down to idle, hunts very slightly for a couple seconds (i could probably fix but meh), then idles smooth (smooth as a factory ls3 at least). pretty much exactly what i was looking for, immensely quieter especially with the npp exhaust closed, and still starts perfectly without a hint of hesitation when cold (about 70-80f ambient right now), lukewarm or full hot. i might even try to set that maf stepdown delay to 0, i suspect that would kill the flare entirely (might have to also add some air back into the airflow table too) but im not sure if it would substantially affect starting reliability.
note that i live in the desert so i have a lot of leeway in how aggressive and haphazard i can be with my values since the weather ranges from "a bit nippy" to "i am literally on fire", if you live in a colder climate you should probably be a lot more careful so you dont end up stranding yourself.

[morepowerjoe]

cutting only the airflow table didnt do the trick on its own, i also had to mess with the maf steady state values as the engine would still continue to high idle with the ecu keeping timing low to keep it under control (lots of fuel + low/negative timing = loud). this is exactly what i ended up doing:

engine > idle > airflow: startup

startup time overspeed and underspeed
-40 to 25: 1 second
(being less aggressive with cuts below freezing for starting reliability (on all tables))
46 to 306: 0 second
(makes the ecu drop out of the startup airflow table immediately once the engine fires, i believe)

startup airflow
-40 to 25: stock
46 to 306: -50% all cells

maf s/s startup
-40 to 25: stock
46 to 306: -50%

maf s/s stepdown
stock

maf s/s stepdown delay
1 second
(lets it kick the engine for starting reliability but nearly immediately drop out of steady state so it can low idle)

engine > spark > advance: catalyst heating

normal, coast, idle p/n, idle gear
copied values from high octane table for same airmass x spark values, interpolated between columns where required
(i have long tubes with high flows so accelerated lightoff is pointless, plus it tends to lope due to low timing which is loud)

st ect mult, ect mult, ert mult, tps mult
0 all cells
(probably makes the above pointless but whatever)

engine > spark > advance: startup

cranking
-5 degrees all cells
(mostly trying to fix a random hot start knock, seems to have worked, likely can be left stock otherwise)

startup flare cont
stock

mult
stock

with all of that now it just flares up to about 1500 rpm then pretty much immediately once the needle hits 1500 it drops back down to idle, hunts very slightly for a couple seconds (i could probably fix but meh), then idles smooth (smooth as a factory ls3 at least). pretty much exactly what i was looking for, immensely quieter especially with the npp exhaust closed, and still starts perfectly without a hint of hesitation when cold (about 70-80f ambient right now), lukewarm or full hot. i might even try to set that maf stepdown delay to 0, i suspect that would kill the flare entirely (might have to also add some air back into the airflow table too) but im not sure if it would substantially affect starting reliability.
note that i live in the desert so i have a lot of leeway in how aggressive and haphazard i can be with my values since the weather ranges from "a bit nippy" to "i am literally on fire", if you live in a colder climate you should probably be a lot more careful so you dont end up stranding yourself.

Thanks for the info!