Trigger
So it's VR, with gaps:
- 60
- 90
- 30
- It's very similar to InputTrigger/SubaruTrigger 55 + 93 + 32 degrees
- with both triggers we must detect (multitooth.c code fire a "trigger_tooth") the shortest gap (gap=30 for Fiat, or 32 for Subaru).
- Than we know we are 70 degrees BTDC (or 65 degrees BTDC in a Subaru)
- in the "MISSING_TOOTH" branch something about the camsync must be checked.
- in the simple case (all grinded but one tooth): if it's flagged
- or the counter to see how many camteeth came since last "MISSING_TOOTH" => sync if it equals the expected N
Correct trigger drawings:
As you see, the trigger tooth is 70 deg BTDC. And there are two other tooth. So the trigger tooth must be the tooth that is approximately 30 degrees(and +/- some degrees hysteresis)distance after any other tooth. Unfortunately i didn't see the wheel myself. The guy who made the engine has took this photo, and the drawing. And i've checked it with him on phone. So i hope that the round direction is good.
Actually, this is the only arrangement and direction that makes sense: inter-tooth gaptimes of 60,90,30 degrees, and trigger-tooth being after the 30degrees gap.
Nice!
Configuration
firmware revision [1.0.27] (or newer required). MegaTune that matches 1.0.23 or even 1.0.19 should match. Just don't adjust primary_trigger variable from MegaTune (it could change for the bad), leave it alone after uploading the correct value from mtt file.
If you change anything from MegaTune, that is on the same page as primary_trigger, verify on LCD or mcd that primary_trigger variable is not screwed.
- primary_trigger=29
- 1: multitooth is on
- 8: advanced filter is on
- 0x20=32: fiatstilo is on
- secondary trigger=..
- distributor does not need camsync
- without distributor, camsync must be used! GenBoard/Manual/InputTriggerCamSync
- wasted spark is OK, use h[2]=00 01 00 01 ..
- config.toothrel_missing=0x4C
- config.toothrel_normal=0x04
- trigger_tooth=00
- another_trigger_tooth=05 # yes, very tricky
- tooth_wheel=03
No change:
- ignchmax=03 # for 4cyl
- rpmk[0]=0b # for 4cyl
- rpmk[1]=b8 # for 4cyl
I commited a fiat-stilo stereo (primary 60,90,30 type + secondary 1 pulse) trigger wav-generator to firmware SVN. The wav-s are OK now (including header), but haven't had time to test it in operation.
As it turned out, the secondary trigger is not 1-pulse originally. Grinder was used to leave only one (big) tooth.
Unfortunately it didn't succeed, the config + setup will be investigated further.
Also, we plan to write code (+config) for the original camsync, which is roughly like 0V at (ATDC cyl1 crankdeg):
- 15..65 (note: mid at 40)
- 220..380 (note: length appr 160 crankdeg)
- note: gap mid at 360+40 = 400
- 420..580 (note: length appr 160 crankdeg)
Here ara the OBSOLETE config files, and a "mde40" log during cranking made with terminal.
- What could be wrong?
- the URL. corrected
The crank trigger could be watch on the top of this site, and the CAM trigger rising edge is about 40 ATDC in crankdegrees. More info come soon.
We use 4 COP coils, connected into the Drive04-05-06-07 in order as cylinder 1-2-3-4
Finally we attached a 60-2 trigger wheel on the crank, and the car is running great now!
Here is the final config:
-Car: Fiat 1,8 HGT 130 hp stock
-Engine: DOHC, 4 stroke, 4 cylinder, 16 valve, with variable intake camshaft by stock, but it's removed now. Race cams are used. And the cylinder head is ported.
-Exhaust: Custom made exhaust system with Supersprint exhaust manifold.
-Injectors: 320 cc/Min injectors. TRhey're hiZ, approx. 14 Ohm. I drive them sequentially.
-Fuel Pump: Stock.
-Ignition: AVR 3.3 with 4 COP coils. They are drived by 5V signals directly from the AVR.
-Idle control: No idle control valve. Throttle body is opened a little.
-Input trigger: 60-2 toothwheel on the crank and a single signal trigger wheel with Hall sensor on the CAM. Sequencial injection and ignition.
The up-to-date config files, engine powercurve and photos will come soon.