Okay then... As a rule of thumb backfiring through the intake means a lean mixture.
Req_fuel looks to be good, and 50% of req_fuel for your cranking pulse seems to make sense. Bear in mind that you're firing all banks for cranking
Settings->Injector Settings so you're getting a load more fuel than you think.
For an experiment, in
Settings->Priming,Cranking,Afterstart set
Cranking Threshold to
1500 this will hold VEMS in its cranking phase even though the engine is running.
If that runs the engine for a time we can be sure that theres nothing happening with the fuel pressure dropping off, and look at the afterstart values, so reset the value to 300 to 400rpm.
You'll be making your life easier as this will have got some heat into the engine and the start-up tests will be simpler.
Currently You have no warmup enrichment so the engine is not getting much extra fuel try:
4.4C = 140
15.5 = 130
26.6 = 120
37.7 = 110
54.4 = 105
71.1 = 100Set
Settings->Injector Settings: Fire banks while cranking to Alternate, doing this will give you a load less fuel in the manifold as you're squirting one injector at a time rather than all six... So you'll need to add more fuel for the cranking pulse, you'll have to juggle the cold and warm cranking values to get the right sort of behaviour as the temperature differs through the season. BTW the afterstart enrichment scaling of 62.7 seems a bit high, you might want to set that to zero and tune the
Afterstart enrichment added value field a little.
Crank the car over watching the PW meter on the laptop. As it cranks, fires, warms up the PW value will begin to drop, you'll see the fuel PWs reduce slowly through this cycle, which I've described here, try and follow the sequence and work out where the fuel is dropping off too rapidly:
Remember to datalog your startup attempts as this gives a load more information that you can mull over whats happening away from the car where concentration may be easier.