InputTrigger/SubaruThirtySixMinusTwoMinusTwoMinusTwo (2011-05-13 12:57:36)

There is a contradiction about crank-pattern inside the Subaru manual (thanx for everyone contributing so we finally sorted it)

Cam info

There is a camsync pulse 45 crank degrees before Cyl 1 TDC, then the second comes 135 crank degrees after TDC

Camsync:

subaru2001-camwheel.jpg

The relative position of the cam (having the camsync pulse coming inside the middle of the long gap) was a reasonable design decision.

Crank:

subaru2001-crankwheel.jpg

crankwheel1modi.jpg

On both pics with the wheel, the wheel turns anti-clockwise. The engine runs clockwise, but the pic is of the back of the wheel.

The engine and the wheel physically turn clockwise, but the above photo shows the back of the wheel, so looking at the pic, the wheel turns counter clockwise.

That confirms: our implementation assumed the above photographed wheel rotates COUNTERCLOCKWISE so the double long gap is followed by 13 tooth, not 16.


Crank Sensor wheel drawing, as mounted on the engine - rotates clockwise: (Beware: the plotted function is wrong: it shows a group of 13 teeth, instead of 16! This caused a lot of confusion)

subaru2001-crankwheelpic.jpg


just thinking

The choice to have the long gap detected at 30 BTDC and 0 TDC is weird.

We can look at it as 15+3,3+12+3


Subaru 36-2-2-2 implemented with camsync: derived from c024 (12 cranktooth + 1 campulse)

  • date:17-december-2010:IS the 36-2-2-2 working without camsync?,1.1.81 as i still have some problems with 6/7, and would the change the crankwheel?/Skassa
  • Date: 22-March-2011, Yes, I ran the engine upon first startup with dualout and no camsync. Then a few minutes later changed it to camsync and sequential.

Than burn, and might need to reboot.

Please measure+figure how to set trigger tooth and TDCdelay.

(tooth 0 is after the long gap after the group of 16 normal tooth). So triggertooth=4 + 90 deg TDC-delay or triggertooth=5 + 60 deg TDC-delay SEEMS appropriate. (The strobe will tell)


Test pattern - codenamed "s362" in wav filenames and signalgenerators

Here is a [wav file] (with CamSync. Inverted to play properly. 735 RPM)


Testing - some [configs] that were used for testing

Since the 2010-06-15 experimental 1.1.76 seems to act properly (36-2-2-2 with camsync or with subaru 6+7 with camsync). Can be tried on bench or engine.


Jason's notes

Here is a [vemscfg file] of the setup described above (trigger settings)

In Jason's engine there is the possibility of using a 4-1 cam signal. It's for the 2004 WRX STi variable cam system (disabled on this engine for now) and those sensors are still there but unused. We should figure out the 2 pulse camsync, but if the 4-1 is easier to handle quickly, I'm ok with that. There is a 4-1 on each cam, but I expect it's sufficient to just read one of the two (just like this 2 pulse cam trigger).

36-2-2-2withcam4-1.gif

Assuming that is the most retarded position. (correct ?)

link to a site, were there is crank 36-2-2-2, plus cam 4-1,

http://www.msextra.com/forums/viewtopic.php?f=131&t=36430

this is what there is on the subaruĀ“s when the run inlet avcs, so NOT 36-2-2-2 and the 2pulse cam wheel


Camshaft-angle control

Firmware originally supported camshaft-angle control with missing tooth primary trigger. But someone on irc requested 36-2-2-2 (without writing details here or there).

We added firmware support for 36-2-2-2 (with the factory 2-pulse camsync) camshaft angle control (1.1.82), but there are still open questions...

Engine has 4 VR sensors in total:

Trigger inputs - 3 should be enough

Output solenoids ?