Fuel cut on boost

[SVTuner]

Hi all my first post and new to tuning GM LSX engines although I have been tuning for many years Japanese Turbo Engines so I know the basics but admit I have a lot to learn

I've just fitted a Magnuson MP1900 to a 2005 LS2. I've made a few changes to the ECM file including the change to 2 Bar OS, modified the Injector Flow Rate vs KPa for the larger 63lb injectors, created the expanded map in the Main VE Boost map, Modified the Power Enrichment EQ Ratio and Enrichment Ramp in. Pretty much setup as per the video guide form the HP Tuners guide Applying 2 BAR SD HERE.

My setup is still running MAF with a 2 Bar MAP sensor, rest of the engine is stock. Car starts, idles and drives fine under light to moderate acceleration, anything substantial and the fuel is cut which I verify from the trip computer instantaneous fuel display.

[SVTuner]

OK I'm wrong, its actually adding too much fuel! You can see on the image below where the hairline is there is a sudden jump in injector duty cycle and is very consistent every time I apply the throttle significantly. Is this where it transfers to the boost map? The settings are PE Enable 15kPa and Enable MAP 110kPa yet this happens at 155kPa???

[SVTuner]

Here's my tune and datalog if that helps. Please guys, critique away

[SultanHassanMasTuning]

what does your AFR gauge read, i think your running way too rich. disable your MAF and then try the car

[SultanHassanMasTuning]

disable your and change your Dynamic

HIGH rpm disable to 8192
HIGH rpm re-enable 500

[SVTuner]

Thanks for the reply. I have not had a chance to hook up the wideband yet but I agree its likely very rich. Is setting the High RPM Enable/Disable to what you have suggested as I understand will avoid using any signal coming in from the MAF?

I find the downloaded image from my VCM quite different from what I was expecting as compared to that used for the LS1. For instance, where is the map when running in open loop mode, that which resembles a similar map to the ignition advance map? How do you tune fuel delivery when referencing ewngine speed and mass air flow voltage? The only option I see to do this is in the Boost Enrich section which only seems to reference against MAP.

Is there some document that explains how the engine management in the E40 VCM derives fuel delivery with MAF and MAP voltages? The help file in VCM suite I find is missing a lot information and generally broad in explanation.

[SVTuner]

Arh, don't mind me, found this very useful article in the FAQ's, Speed Density tuning E40 PCM's write up.

[SultanHassanMasTuning]

cancel MAF its very differen than LS1 formats

[SVTuner]

cancel MAF its very differen than LS1 formats

Do you mean delete the MAF sensor? I know a lot of people do this but to what benefit?

[SultanHassanMasTuning]

newer platforms have IAT sensor incorperated in the MAF. Keep Maf plugged in or buy an IAT sensor and wire it and mount it in the same spot

[loppad]

Your current PE table is set for a 8.61:1 air-fuel ratio (14.768 / 1.704 = 8.61). A very rich mixture even for a supercharger. Try 11.5 up to 5000rpm then 11 for the rest of the range just for protection. Set the MAP PE enable to 45 or 55 (I've seen this up to 90 in some cases) otherwise you'll be in wot very easily because of the supercharger pressure and your fuel consumption will increase. Don't forget to set the PE delay RPM to 1000 rpms, is not a good idea to wait until the 5000rpm to enable WOT in a supercharged car.

[SVTuner]

Thanks for everyones help. I've implemented the suggestions by everyone and now am getting places. I installed the wideband standalone (not wired into VCM Suite) and watched the AFR's and tuned to around 11.7:1 using the PE and Boost enrich maps. I still need to optimimse the spark advance map as there is some pinging at low load but I'll tackle that when I get some time. Going forward I would like to learn how to tune with the MAf but I need to get my head around some basic principles like Speed Density.

Once again thanks very much

[SultanHassanMasTuning]

^not a problem, its what we are here for

[MikeOD]

Thanks for everyones help. I've implemented the suggestions by everyone and now am getting places. I installed the wideband standalone (not wired into VCM Suite) and watched the AFR's and tuned to around 11.7:1 using the PE and Boost enrich maps. I still need to optimimse the spark advance map as there is some pinging at low load but I'll tackle that when I get some time. Going forward I would like to learn how to tune with the MAf but I need to get my head around some basic principles like Speed Density.

Once again thanks very much

Did you tell the PE table to target 11.7 and then adjust the VE table to make the AFR actually hit 11.7? If not, the knock you're experiencing may be based on an incorrect airmass calculation causing the wrong (possibly too much) spark advance. If you just adjusted the numbers in PE and BE until your wideband said 11.7, then that's a big cause for concern...the car may not be able to fuel consistently in the future, and as mentioned, your spark advance is looked up based on incorrect values.