Injection Timing During Cranking

I am trying to adjust the injection timing during cranking for my LBZ duramax. I have used several different values for the 300 & 600 RPM and have yet to note/observe a change from the Virtual Dashboard.

What do I need to do in order to advance injection timing? My understanding is that all you need to do is modify the map, save the changes to a .Tun file, then reflash the ECM. Since there are 5 versions of the main base injection timing, I made each map (A-E) to be the same.

Is there a separate map for cranking? Why isn't it responding to my changes?

In the LB7 / LLY ECM's there was a cranking table, the Bosch ECM probably has one too but as yet we've not found it. I've bumped it up the list of things to do for you :)

Cheers,
Ross

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Originally Posted by GMPX

I've bumped it up the list of things to do for you :)

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Haha. Ross you are too kind. You guys really are helping me out a lot and I truly appreciate the effort. Hopefully some of my questions have helped spark ideas for your LBZ software development.

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Originally Posted by thetallengineer

I am trying to adjust the injection timing during cranking for my LBZ duramax. I have used several different values for the 300 & 600 RPM and have yet to note/observe a change from the Virtual Dashboard.

What do I need to do in order to advance injection timing? My understanding is that all you need to do is modify the map, save the changes to a .Tun file, then reflash the ECM. Since there are 5 versions of the main base injection timing, I made each map (A-E) to be the same.

Is there a separate map for cranking? Why isn't it responding to my changes?

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Why are you wanting to change the timing during cranking?

My engine is connected to an engine dynamometer and therefore has extra inertia to turn during cranking. The stock starter has difficulty spinning the engine fast enough for it to start running. I was going to play with the timing to make a more aggressive starting strategy and compensate for the additional mass.