VEMS on a Volvo V70N 5cyl engine
Please have a look at my homepage: http://www.hilmersson-racing.com (Swedish)
The project page: http://www.hilmersson-racing.com/start.asp?show=e
Specs:
- 5cyl, 2.4L
- 60-2 cranktrigger, VR sensor. Note: Missing tooth, not missing gap
- should be OK, but watch wheel-error in case you experience RPM-dropouts
- 1 pulse on cam, HALL sensor
- Ignition with active coil's directly on the spark plugs.
- Firmware 1.0.36
Questions:
Ignition
- The active coils on this engine needs +5V signal as trigger. The GenBoard has 2 IGBT + 6 logic-level outputs.
- the logic level outputs are 0V / +5V (actually, high level is +5.5V for v3.3)
Injection
- How do I set the injection end angle? I mean the angle in crank degrees when the injector is activated. This should be when the inlet valve is open (at lower loads)
- adjusting the injection phase is not enabled in current released firmware. It is planned before the racing season, because there are some requests. It does not effect maximum power, but (when tuned right) makes better efficiency and emissions, and smoother running of aggressive-cam NA engines.
When playing with injection-phase, one can measure upto 5..8% change in output power, even if only injection-phase is adjusted, and all other settings are left the same. The reason is that the fuel sent out the exhaust varies in function of the injection angle (especially with huge cam-overlap at relatively low RPM). But regardless of the injection angle, the maximum power is the same (within 1% : due to higher limits when cooling the engine with the added fuel that escapes the exhaust unburnt: this is reached anyway, with the default injection-phase that is used now ), because the tuner always adds the fuel that escapes the exhaust (of course, leaning is not allowed).
- What is the default injection phase angle, that is used now?
- A: In the current firmware, injectors are driven right away after trigger, that is approx ign_tdcdelay setting. //Emil Larsson (contact me when you are about to start the engine, i can stand by for phone support or something)
Trigger
Are these config settings correct for this engine setup with 60-2 cranktrigger?
- primary_trigger=01
- secondary_trigger=18
- tooth_wheel=3A
- trigger_tooth=05
- adjust this as you need. Also, take note of ign_tdcdelay
- another_trigger_tooth=18
- tooth_wheel_twidth1=02
- tooth_wheel_twidth2=06
Seems good. Seems to match GenBoard/UnderDevelopment/FirmWare/TriggerRelated
I have problems with the trigger. Sometimes it works perfectly and sometimes it doesent work, with the same settings. When it doesent work, the RPM reading in megatune goes down to 0 for a short time at the missing tooth (I think) while cranking.
Log InputTrigger/TriggerLog to check VR polarity (it might work with reverse polarity, just not reliably)
Config, tables and megatune file:
http://www.hilmersson-racing.com/config.txt
http://www.hilmersson-racing.com/tables.txt
http://www.hilmersson-racing.com/boat050820.msq