Ignition parameters for odd fire coil type configuration.
As I understand, the Marelli microplex logic for starting the ignition is:
| On CamTooth 1 | START COUNT Crank teeth |
| On CamTooth 2 | If CrankCount=2 then START IGNITION, (next cyl. is c2 90° from here |
In software they simply made a switch for the 12 cases
given by the 12 teeth met in a 720° cycle. Also they simply put a
constant 120° dwell time since there is always 120° (that is 30°+90° or 90°+30°)between the 2 previous teeth and the firing tooth. See here after
BLEU : IgnitBiturbo1000.wav - JAUNE: IgnA - VERT IgnB
Question
Lets note the 6 tuples of 2 crank teeth which are seen by the VR sensor during a double revolution of 720 ° by the following:
/t01/.30°./t02/ .. 90°.. /t03/.30°./t04/ .. 90°.. /t05/.30°./t06/ 90°
/t11/.30°./t12/ .. 90°.. /t13/30°/t14/ .. 90°.. /t15/.30°./t16/ 90°
Indeed cylinder numbering is not useful at this bench test stage. Although things are more involved we just want to exercise the VemsTune capabilities as a first attempt and observe with a scope what's coming out.
So lets us ask Genboard to fire 10° before the following teeth
/t01/ ..... 150° .... /t04/ .. 90°.. /t05/ ..... 150° ....
/t12/ .. 90°.. /t13/ ..... 150° .... /t16/ .. 90°..
What are the options to set from the VemsTune menus?
Answer
- download the config from MembersPage/OddFireSixCyl
- dragndrop file to relevant dialogs ("primary trigger", "reftooth table"). This is the quick way to import the displayed settings (changed entries change to red)
- the ign outputs must be set to your ignout wiring
Can we do odd firing with coil type triggers? How?
The config used the individual cylinder spark delay.
Anyway I don't even know on which crank tooth Firmware 1.1.90 start counting. I should make a triggerlog next time.
As for the use of spark delay, I think I have understood :
Because of the odd fire configuration of genboard, it remains 6 reference trigger pulse per double cycle from the 12 crank triggers, hence they are 120 ° apart. That is
/t01/. 120°.. /t03/.120°.. /t05/.. 120°
/t11/..120° /t13/ ..120° /t15/..120°
or
/t02/. 120°.. /t04/.120° etc depending of when firmware does the sync from the cam trigger (I have to find out that)
I found out the delay parameters from the VemsTune menus "Cyl separated Spark delay" and was surprised to see it is already set as one wanted, this is also define, I presume, by the table h[3] of the config file (MembersPage/OddFireSixCyl):
h[3]=00 78 00 78 00 78 00 00
because 0x78 = 120 = 4*30°.
Indeed if we note d03,d11, d15 the ignition events delayed by 30°, we get what we need:
/t01/.150°. /d03/.90°./t05/. 150°. /d11/.90°./t13/.150°/d15/. 90°.
Help for ignout config
So that we can help with ignout config that matches your wiring, fill this in:
- What is the exact position of the 2 primtrig pulses coming after the second sectrig pulse ?
- What is the cylinder that follows ?
- which ignout is that connected to ?
- than list the remaining (5) cyl / ignout entries
- always mark the angle separation between the cyl/ignout entries (in a separate line, to be clear, 150 or 90 degrees)
Answer
I am not yet at this point. I would connect the firings lines (with diodes)* for the bank A all together, do the same for bank B and fire the engine through the distributor the same way it is done with the Microplex (we are still far from there).
I finally understood that this is useless since it is possible to drive freely any ignition event to any ignition output of the genboard (yes Versatility)!! and this is already done by the config file since
h[2]=70 40 70 40 70 40 70 70
As we see only 2 output ports are used in order to fire the cylinders of bankA or bank B.
Of course now one needs to know which is which and the Triggerlog which now records the ignitions events would be of great help for that.
Copy of the biturbo ignition map to genboard
This biturbo map is a 16x16 array where lines are for MAP and columns for RPM. I found out the scale for the MAP, I also need the RPM scale precisely...
Inj outputs - same order as ign
Use the same injout entry as the ign (if topmost ign is, say, cyl3, topmost inj should be also cyl3 output for unbiased inj-angle positions).