InputTrigger/BmwDoubleVanos (2012-01-25 18:20:39)

BMW has many different [VANOS] systems. Only the M car engines have dual solenoids.

The most interesting app is the double-vanos with 4 solenoids and 3 VR-sensors


Fero reported that Double VANOS works perfectly

Information needs some cleanup from

especially trigger setup and initial cam-position target tables.


GintsK currently works at M5 S62 V8 project where we trying to keep intake side VANOS functionality. Exhaust - blocked at fixed position. So on one intake cam exhaust trigger gear installed for camsync functionality (it is not possible to sync from even spaced 6 tooth gear). Engine works so far. VANOS also! But with some oscillation problems. So I have some questions: http://vems.hu/vt/help/v3/v3_camshaft_angle_control.html says:

Avoid the word "closed" or "open" because easy to misunderstand (a valve can be either closed or open when powered or unpowered). Use the word "powered" or "unpowered" for the solenoids (that's what can be set from software).

Currently our solenoids also powered ?

What is recommended pwming range?


The intake VR polarity was originally wrong (rising edge)

BMW_S52_doubleVanos_correctIntakePolarity.png

Note that


Watchout

When doing the test-install, we've seen several things that caused problem. This list is useful for installers.


Historical:

Before we identified the torn flywheel dampener (see above) we didn't understand what caused the trigger-error and unintentional "6500 RPM revlimit". We made intensive benchtests until the bench-RPM was beyond 11000 RPM, the VR-adaptive-hysteresis minimum ("runout") was well below 60% and all was confirmed good.

From engine-recorded ~1190 RPM triggerlog, Marcell extracted a 16 second section:

http://www.vems.hu/files/Fero/BMW_M3/BMW_doubleVanos_correctIntakePolarity_nicePart.zip