Hi!
My name is Sam Johnson. I live in Victoria BC, Canada.
My project is an Onroad/Offroad Jeep. I am installing a GM 4.3L V6 engine
- sequential EFI (Bosch 0.280.155.968 injectors)
- wasted spark ignition (Bosch 3x2 coil)
- a single Masterpower MPR R6164-12 turbo, 60mm external wastegate (with 4 way boost control solenoid)
- Air to Water aftercooler.
Trigger
- 60-2 crank
- Primary trigger is a Gen4 58x GM sensor (grey in color.) It is a 3-wire sensor with a 5V supply, ground ref and signal output. The hardware is packaged in a round body housing a magnetic sensor and solid state electronics. The electronics convert the AC signal to logic level 0-5v square wave signal. It outputs a (supposedly) very clean waveform. What do I need to do for the vems to correctly interpret this signal?
- it sounds like a plain HALL input should suffice
- Here is pic of the crank reluctor (linked from EFI Connection web site.)
- 4x cam sensor (?)
- can you detail this ? Is that a VVTI V6 with 4 cams (2 intake + 2 exhaust sensors ) ?
- or 1 camsensor with 4 pulse-pattern ? How are the pulses timed (they should not be evenly spaced, at least that does not make sense for camsync/secondary trigger)
- secignore can be used to neglect eg. tooth > 13 (just an example), but of course sectrig pulse should only come every 2nd crankrot (tooth 0-12 in the example)
There is a single cam sensor with an unevenly spaced 4 pulse-pattern. Here is a picture of the cam reluctor:
I am making an effort to find a waveform depicting the cam pulses referenced to crank position.
Just capture triggerlog with
- sectrig=falling
- and sectrig=rising
Hoping to use VEMS genboard to control the engine with wideband EGO feedback and pre-turbo EGT thermocouple for tuning. I intend to get anti-lag working with my 3 speed automatic transmission (obviously anti-lag NOT required for shifts, only for closed-throttle deceleration and launch.)
Ion Sensing?
Is this tech dead? I notice both vems and B&G were developing Ion Sensing boards back in the early 2000's but things seem to have gone quiet since then. What's happening?
- it is difficult to reach a sensing resolution that is really useful
Is there an opportunity to help with development?
- possible, discussing a bit about that on another channel
Also hoping to use genboard on-board MAP sensor for dynamic BARO correction with an engine-mounted Bosch TMAP (2.5 Bar) as the primary MAP sensor.
- baro correction can use external sensor (115 kPa, or same range as internal MAP sensor are most common to use, but... )
Do you mean to say " baro correction can use INTERNAL sensor " ?
- yes, you can request in the order comment "an internally mounted baro pressure sensor connected to mcp3208" (dynamic compensation during running - dynamic baro compensation is required for mountain rally or airplane)
- or even internal or external MAP sensor can be used for baro compensation if it's sufficient to sample barometric pressure at boot-time
- a common method for engines rarely driven at a much higher altitude than it was tuned... -20% pressure that requires appr +8.2% fuel can be handled easily by tuning +8% rich and leaning with wideband-lambda-ego.
Also of possible interest to the community is my effort to model the engine in Ricardo WAVE. I have a working model now but am still calibrating with dyno logs from similar engines. Once calibration is complete, I hope to link the model to a SIMULINK model of the VEMS. Has anyone modelled the VEMS firmware in SIMULINK?
- Probably not