Are we talking degrees from TDC or degrees from the original seting?
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Good morning Kristijan
My V10 ram has no distributor but will advance the time about 30 degrees more than it is already set when switched to wood gas . The truck does this automatically .
On my 5.2 v8 ( years 92-96 motors ) after they have warmed up I will turn the distributor and the time will advance 45 degrees more than gasoline setting and then moderate back some. A very noticeable increase in rpm and power .
Many of the older motors I have gasified ( 460 ford , 390 ford ,400 ford , 87 v-6 dakota , 91 5.2 v-8 dakota ,IH tractor ) I could tell no difference in power by advancing timing .
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I’m not a fan of these sensors but I think the crankshaft sensor takes all it’s reading relative to TDC of the number one piston.
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I have my distributor set at about 32° at idle, stock setting is 5-8° for gasoline. The high torque mini starter has no problem cranking up at this setting and the fly weights in the distributor max out at 45°. I never did run it on stock timing in woodgas so I don’t know that there is a power difference but I have never had a mixer box puff???
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Good solution setup Kristijan.
Second hole mounting will physically only allow a minimum 10-15 degree advanced from the standard sensor position.
Now here is the uncertainty . . . . MANY later electronic systems put the crank sensor at a true 45, or 60 degrees ADVANCED from a true cylinder #1 top-dead-center!
Why?
Easier; with a quicker system active response, to get the base input information EARLY, and then calculate a timing LAG from that (but sill advanced from a true TDC) for the very next cylinders’ in firing order, power stroke event.
With a base input sensed close to TDC then having to ADVANCE calculate it can only be applied two crankshaft revolutions later. Probably what you have.
And you are different-circumstances asking on woodgas with your much higher boosted compression pressures.
Joni said on his GM four cylinder once compression boosted he no longer needed, or benefited from much additional ignition advancing over stock gasoline.
Regards
Steve Unruh
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Sorry for a late response. The numbers I mentioned are all extra degrees from the stock setting.
Things like combustion chamber geometry are slightly different on every type engine. I guess you will have to gamble some.
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So guys, I have a question. Why is a knock sensor used in the engine management system ??? And if an increase in the compression ratio leads to a more intense combustion of the mixture in the engine cylinder, what prevents the knock sensor from doing its job? 
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O.K. It gets a little complicated from what a knock sensor does . . . to how it is used.
Knock sensor have no power input to them. They output a stressed crystal made voltage. Can have measurable microamps. And that voltage and microamps will have a detectable amplitude and frequency. A wave form.
So the design engineers study the engine to be controlled for the best locations to detect combustion chamber pressure spiking knocks.
Originally; and still, most designers use the knock sensor to stay far, far safe away from conditions that will produce stressing knocks. By adjusting the engines spark timing and fuel/air ratios. Once knock sensor activity is detected the software immediately jumps the timing back by multiples of degrees. At least 3, up to 8 degrees. Then later will slowly ease it forward one degree at a time. Checking. Checking. Knock activity detected then jump back and repeat.
Primary sensor are needed to determine base nneds to run conditions.
Secondary sensors like a knock, or exhaust oxygen sensor are feedback “are we achieving what we predict?” sensors.
It became very apparent by the late 1990’s that both GM and Toyota were using the knock sensors activity to get best economy, and best power fine tune.
Seen no knock activity, they would in one step jump ignition timing ahead 3-5 degrees. Then detect for a very short time frame. Then jump ahead again in a multiple degree single step.
Once knock activity is detected; then, only then, back off only one degree and recheck. Only another one degree at a time until just out of knock.
Realize the conditions to make knock can change with just a traveling altitude change. A weather front blowing through. A refueling stop.
Or long term by in combustion chamber build ups. Injectors nozzle build ups. Electric fuel pumps wearing.
I am somewhat dated back to 2005-07. Only knock sensor voltage made was monitored back then.
I am sure some systems now detect for microamps intensity. Or produced wave patterns now.
Steve Unruh
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Joni I had to search back in my experiences to try an answer the last you asked:
" . . . what prevent the knock sensor from doing its job?’
Unfortunately, nothing.
USofA after 1996 and later EU emissions system demands required systems to self-test sensors circuits and sensor functionality.
Ha! So a couple of vehicles that had more than one broken timing belt incidences (requiring cylinder head rebuild with machine grind trueing of the head surface) the compressions became too high for regular grade of fuel.
Tried demounting the knock sensor. Did not work. Circuits would not test O.K. on circuit self-tests.
Tried remounting the knock sensor to a “quiet” part of the engine. Would later “fail” self-testing. Set the engine light. And eventually the engines would go into low power limp-in mode. Sytems self-test by short-term advancing the timing to intentionally make knock to be detected. “Quiet” remounted sensors could not hear the intentional made knocking.
The one vehicle was a 2004 four-cylinder turbo charged Misubushi coupe sports car.
She liked the car. Liked the smooth rush of power. She convinced herself that 15% more expensive Premium high-octane gasoline was better for her car anyhow.
The other car was a base economy 2002 Kia Rio.
Owner was upset to have to use more expensive Premium grade fuel.
As I said the easy work-arounds did not work.
He would need a new stock cylinder head . . .
or a risky doubling up; using two cylinder head gaskets.
Many later years systems mostly have the programming range to allow for enough flexibility to use our pump rated 87, 89, and 92 octane fuels.
I think - maybe - they would woodgas just fine.
S.U.
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Today l relocated the crank sensor.
Put it 3 cm forward on the flywheel, shuld corespond to roughly 10° aditional advance. I still have space for aditional 5°, but it might be pushing it.
The engine runs good on petrol. No cnock and good power.
Woodgas, ha! Thats more like it! I squeezed a nother 15kmh out of it on 100% wood, the engine likes to rev now! Much better torque too. Now l reached a point where l can say the sistem reached minimal standards performance wise, so that l can takeoff nice and stay with traffic without blending in any petrol. Its no race car thugh, still 80kmh is top speed. May reach a bit more if l throw the bed cover off. But this is good enaugh! And it runs on the same setting with both petrol and woodgas.
I have noticed thugh, the sistem may be a bit water hungry. I squirted some water in the intake and the rpm went up, even thugh l use damp charcoal. If so, l may run dry char with water injection in the future. Will see…
For now l am pleased!
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If it appears water hungry, would damp wood chunks blended in be helpful beyond the damp charcoal?
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I’m glad you’re back in business Kristijan. Time to start counting $$$-charcoal shovels again 
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Marcus, l now have a true 8" WK hearth inside, it can run on raw wood chunks or chips or moistened charcoal, or a blend of dry charcoal and wood chunks but l found wet wood is a no go in any gasifier. Even in a mix of dry charcoal and wet wood, the temperature inside is high but the wet wood cant combust fast enaugh and by the time the wood starts burning well the chunks have migrated too low in the gasifier and start to make tar.
JO, l baked a batch of chestnut wood the other day, absolute shit when it comes to BBQ charcoal but the gasifier isnt picky 
about 150$ worth of dino
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IV been concerned about that the whole time running my truck you can see in the videos I have rather large chunks making it to the nozzles regularly being damp and saw cut. I still have about 14" of charcoal below the nozzles so it has not made any tar yet thankfully. If I have wet wood I load it at the top of the hopper hoping the heat of the char bed gets it dry before it gets to the fire tube. Still collecting crazy amounts of condensation though
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You are using two bags of wood to get to and from work Marcus. If it were me I’d add an insulated barrel somewhere and fill it with wood and run the exhaust gas through it while I drove. Or maybe a flat hopper over the existing bed that you could just rake the fuel out of. Same condensate capture you are already using. More armchair quarterbacking.
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Is this actually a problem? Heck, your truck goes!!!
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No complaints! She goes everyday
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Kristjan, I’ve been thinking a bit about mixing water vapor in your system, you use moist charcoal but the drying takes place over the hot zone and the humidity rises up in the center of the action and only dry air is blown in. Your gasifier has air intake through the pipe from the top, if you added an opening for steam entry on the inside it could improve the gas.
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Ha, fun did not last long. From my part, the sistem runs good. Now, its the engines part thats playing tricks on me.
I have also seen this months back when l first gave the Škoda a sniff of woodgas.
Drove home on woodgas last night, was a wery pleasant drive. Stopped, swiched on petrol for a few seconds, to flush the injector of any potential soot buildup, then l shut off the engine and went to bed. Everything was perfect.
This morning, the engine played tricks on me. No idle (on petrol), no power. Barely kept it alive. Squirting petrol in the intake imediatly reved the engine, means the engine is starved of gasoline.
I belive the reason is l have a steep mountain road the last mile before home and its no way l can drive 100% woodgas comfortably. Even in gasoline mode, engine still sucks woodgas. I think l run too rich and the computer remembers the setting, cutting the fuel down on the next drive.
After a few drives the problem went away the last time, so did today. Well, kinda. Still not perfect. Will see on the drive home tonight.
Or, a sensor of some kind got dirthy. Any thods?
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