Customer has a drift car, BMW with installed Dodge Viper 8.3liter V10 engine.
Engine is odd-fire V-10 (90-54 degrees). Similar to MembersPage/ThorbjornEngdahl/VIPER
- HALL,HALL (both crank and cam sensors HALL)
- firing order 1,10,9,4,3,6,5,8,7,2
- odd fire TDC 0,54,144,198,288,342,432,486,576,630
- WHEN is the TDC following/relative to the sectrig?
- it matters little which cyl it belongs to (but take note if you know)
- considering that internal sync-points are the pulses after the short (18 deg) gap
- determine per cylinder ignition delay: alternating 0,18 ??
- and the 8 entries of reftooth
- similar to Maserati config (subaru6+7) but 10 tooth configured: config.tooth_wheel=0a
- apparently 5 channel ignition (ignchmax=04) must be configured finally, but temporarily set 8 ignchannels so the (3 phantoms) can be set properly eg ignoutputs: 3 2 1 0 7 (3 2 1) .. .. the 2 invisible ghosts are automatic: 0 7 in this example. Only change to 5 channel ign after all 8 are configured.
- in vems v3 firmware the reftooth is internally 10 entries, 8 configurable + (2,1) wired in: 8 channels configurable freely: 0 9 8 7 6 5 4 3 (2,1) the (2,1 is invisible). Useful for VIPER if 5 ignchannels are configured AND number of tooth on wheel = 10 (with config.primary_trigger=A2 or E2 if auditrigger is configured, divby2 of course).
- the 2 invisible ignout entries are same as [x-5] ... perfect for 5 cyl wasted spark: A B C D E A B C (D E)
- the 2 invisible per cyl sparkdelay entries are same as [x-8] which should be good if eg 2 values are alternating like X Y X Y X Y X Y (X, Y)
- check spark at initial sync
- theoretically auditrigger div2 config could work (totally hiding the odd tooth from timing calculation) using 5 wasted spark coils and 2 injectors per inj output (benchtest result?)
Primary trigger is HALL and trigger type is apparently coil-type (flywheel has 5 pairs of teeth, see photo).
EDIT: Trigger log: both primary and secondary trigger: http://www.porsche-foorum.org/album/displayimage.php?album=lastup&cat=0&pos=0
- [same content in zip]
- The 72 deg (10 cyl) seem to be 18+54 (18 deg=15.5 / 61.6 msec * 72 deg)
- and 18 deg + sectrig comes after 24 crankdeg + following primtrig after 30
VEMS reads RPM but throws trigger errors
- with what .vemscfg exactly ? Or better .vemslog ?
- The config is definitely not good, the spark time is not consistent.
Is it possible somehow to mask the 2nd tooth of each pair so that VEMS treats the primary trigger as coil type with 5 teeth?
- auditrigger divby 2 (should do just that, the primary setup to test on bench when applying viper-trigger)
- search oddfire or Maserati eg. MembersPage/FPhil/CoilTypeOddFireConfig
- the Maserati code was at some point made highly specific to the maserati (for quick-startup), and might not be suitable for other (non-6 cyl) engines. However, after v3 fw 1.2.2x it was made more generic again and might worth some tests while benchtesting viper trigger.
- (fphil)I had other configs setup depending on the parameters "TDC after trigger" and "Spark delay". Better to work on a bench.
Secondary trigger is HALL, pattern is unknown at the moment. UPDATE: cam trigger is "half-moon" style: one teeth which is 180 degrees wide.
Ignition system is wasted spark, using 5 ignoutputs
- (fphil)I have tried wasted spark ignition for the odd-fire 6 cyl. It works bad even when the advanceis low.