What brand/model is LS1

[Charlescrown]

Just a quick bit of info needed. What make/model ECU is used in the Holden LS1?

[VL400]

12200411, often mentioned as just a '411 PCM. Or 12586242 is the later 1Mb version.

[antus]

Yep, delphi brand (what delco electronics turned in to), often also 0411

[Dylan]

Out of interest did the 411 PCM's have the charge temp adjustable like in the 808's? Not sure what it's called in the later one's.
Mafless mod in particular.

[antus]

Yes, from EFI Live, stock holden OS 12225074:

Code: Select all

{B0109} Blend IAT With ECT	Yes	

Yes means the PCM will blend IAT and ECT to determine the charge temperature of the air entering the cylinder, used in VE calculations.
No means the PCM will use the IAT exclusively as the charge temperature.
The blend weighting between IAT and ECT is determined by {B4901} "Charge Temperature Blending".

See also: 
  - {B4902} Charge Temperature Filter
  - {B0101} Main VE Table

Only the following values may be entered into this table:
  - No
  - Yes

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Charge Temperature Blending

The PCM calculates the charge temperature (in degrees Kelvin) using the following formula
273.15+IAT+((ECT-IAT)*factor) where factor is obtained from this calibration.

At low airflow "factor" is closer to 1 which weights the charge temperature in favour of ECT.
At high airflow (>150g/s) "factor" is closer to 0 which weights the charge temperature in favour of IAT.

The theory being that heat (ECT) is transferred from the heads and manifold after the IAT has been measured and prior to the air entering the cylinder.

If factor is 0, then the charge temperature will be IAT, if factor is 1, then the charge temperature will be ECT, other values for factor will blend the charge temperature between IAT and ECT accordingly.

In later operating systems this calibration may be controlled by {B0109} "Blend IAT With ECT".
Early operating systems will display the above calibration link as "not found".

See also: 
  - {B4902} Charge Temperature Filter
  - {B0101} Main VE Table

[Dylan]

Interesting a mate has a worked ls1 in a very tight engine bay. He had it tuned by a reputable tuner.
He drove it on a hot day and ran like crap. Rang the tuner and he said don't drive it kn a hot day heat soak will make it run rich. The air temp sensor is in the in the intake pipe.
Has anyone ever moved it down into a runner like the VN runs?

[antus]

I'd be first checking the sensor is the right one, stock location, believable data logged, and also the coolant sensor. Also check what else is changed, including injectors and if so the dead time settings. It could easily be something else. Air temp has more to do with spark adjustment, as it'll ping more easily under temp. I cant be sure from what you've said but I'd be inclined to think more about injector calibration.

[Holden202T]

yeah or a lazy tuner that hasn't tuned all areas of the tune!

what sort of response is not drive it on a hot day!

[Dylan]

They are different injectors i think they're the Bosch green top.

[antus]

Yeah, worth getting the part numbers for them, research the dead times, and check them in the tune. Then hope they're not clones from alibaba with flow rates all over the shop.