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'''This page is dedicated to Low-Z injector tuning, at BMW M30B34 turbo engine.''' Injectors are the stock ones for this engine: Bosch part no. 0 280 150 200, maybe 270-300 cc/min @3/3.5bars (different sources say different values). R=~3 Ohms. ---- My previous calculation was for required fuel: Req_fuel = 6.49 * (D / N / I) = 6.49 * (3450 / 6/ 300 cc/min) = 12.44 ms = 0x7C Which seems to be on the high side. (So the injectors are not 'so' big for this displacement). But engine was flooded with those values, finally I ended up with a Req_fuel of 5ms, and still I've got VE values of 20-30 (decimal) near idle. Idle is ~1ms pw. I guess something is wrong with injector settings. I worked with the following settings: http://quasar.dynaweb.hu/~lezsi/bmw/attila/attila-injsettings.gif I guess a PowerFlyback couldn't be a bad choice here. If you're interested [http://quasar.dynaweb.hu/~lezsi/bmw/attila/datalog200512302240run.xls here's] a datalog with starting, badly oscillating idle, and cruising home with unmapped car, etc. For analysis I suggest my actual favorite: [http://www.ideasandsolutions.biz/MegaLogViewer/ MegaLogViewer] the first program which knows everything I wanted, not buggy (just a bit slow -java) * Have you tried divider 2 (or is it 3 for 6cyl? I dont know), so no injection on every rotation -> twice longer pw. ** I'm not sure about inj calculations (and manual doesn't cover divider config), but let me guess: if (alternate+1)*divider should be equals to 6 in my case, then if I use divider=2, then I need to use alternate=2 which means to me that I have to form 3 injection banks? *** Divider has nothing to do with alternate, it only divide injection trigger pulses. No need to change injection bank or alternate. ** If above equation is true, using divider wouldn't twice inj-pw but cut into half! Please correct me. *** Divider means you get squirt every Nth (spark?) trigger, if injection trigger times cut half to get same amount of fuel pw needs to be twice longer. No need to double your VE or anything else. * Powerflyback may help if pw is near 1mS, someone else may know it better. If (injpwm14 + multfact(VBatt) * injpwm6 ) > 100% (at certain - low enough - VBatt) than it is railed at 100% (since that is the limit of the duty) * To keep same current, example if pwm@14v=30% pwm@6v=70%, so is injpwm6=40% correct? Or what is this multfact(VBatt)?
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