I've been digging back into this lately and notice a discrepancy between the spreadsheet posted in this thread vs others on hptuners. IDK what's right and either way a calculator is only going to get you so close. There's different theories on whether or not it's better to advance the end of injection or delay the end of injection with big cam swaps... I think generally delaying is more well liked based on what I've come across.
Either way, your best bet is to probably do a little trial and error and see what your car likes. I am going to fully warm up the car to keep that variable constant, and then try increasing or decreasing B3702 value in 0.2 increments, datalog idle conditions and see how they look. I'm going to run closed loop, LTFT disabled and look for the setting that gives me lowest fuel trims, i.e. least amount of fuel required to maintain standard 14.7:1 idle. This should translate into what's most efficient for my new injectors, cam timing etc.
I just changed injectors and figured it was good time to dive into this before re-tuning the whole fuel map now. I'm using Deka 80 lb/hr injectors and a B3702 value of 5.35 at operating temp and with reasonable VE table values my fuel trims were +25-30 percent, so something seems off and I want to see the effect that injection timing has before just adding to the VE table. My values were changed to put injection earlier, but now I run a totally different style of injector so the theory of spraying fuel onto a hot valve to evaporate may not work out as well. If I want to delay my injection until after EVC (@ 0.050"), I need a value of ~5.6 or ~6.3 depending on which calculator I want to trust.
If someone has a better technique let me know!
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