I am planning to run rocket fuel in my wk dakota build. Exactly what is the ratio of wood to charcoal? Engine grade charcoal ( 1/4 to 3/4, no dust)? Also do you same restriction and depth as with wood only?
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Randy it would be a good idea to build it as if youāre running raw wood. Rocket fuel is just a bonus you can do. I forget the ratio, Bob I think uses 10 or 25% charcoal?
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Thanks so basically just better gas or is there other advantages
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The charcoal helps make sure youāre not depleting your char bed on hard pulls or higher speed highway driving, and it absorbs moisture from the wood. The WK is already really good at extracting moisture to begin with, so itās just a nice bonus effect.
It can be as simple as taking your charcoal from the ash clean out and sifting the dust away, then pitching it back in.
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Great. Sounds good to me. Do you mix wood and charcoal before you fill hopper or as your filling it.
You could just bag it up together, or fill it up in layers. I donāt think it matters a whole lot, I havenāt done it yet.
Hello Cody and Randy .
I cannot tell much difference in power or performance when adding the char back to the gasifier but the efficiency ( miles per pound ) improves .
Too much small char and the motor has to draft harder. You will be making very good gas just a little less of it .
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Ok thanks for the info. So does charcoal need to sized or just screened toremove dust and fines. The main reason Iām thinking of going this route is i ve access to a lot of pallets. Turning them into charcoal i can pick up nails with a roofers magnet.
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Iād go with the Engine Grade size range and bigger.
No smaller than 1/8" and no bigger than 1" is Engine Grade charcoal for an Updraft. But Iād call it Way Too Big when theyāre about golfball sized when it comes to a downdraft.
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If you use pallets make sure the nail heads will go through the grate hole or they will be hanging from the grate.
When I rebuilt my firetube and pulled the WK Gasifier apart, I found lots and lots of nails hiding everywhere in the ashes of the gasifier.
Bob
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I cut slots in grate so am good there. Am trying to keep nails out but am sure some will slip by
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Mr. Wayne, I also struggled with a tight carbon bed in the beginning, until I started using the lower nozzle, it works really well, now I know that I can always recommend it, even for the WK system, where I would increase the restriction opening and put a flat bottom a plate instead of a grid and a nozzle with a 6-8 mm inlet opening in the middle. Guarantee of satisfaction and smooth operation. 
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By ading charccoal, among the things others described, you fill the space betweed wood peaces. So:
- you gain more range
- there are less convection currents in the hopper. Less heat loss and cooler sistem.
The later can also be a disadvantige. The condensation part of the hopper doesent work so using wet wood is a no go! But if useing dry wood its no problem as the added charcoal will consume the exess steam.
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Hmm, I thought it was the other way around, that I could have wetter wood, because the coal would increase the heat.
Do you understand why my lambda probe says that there is too little oxygen when I run on dry spruce, or rocket fuel?
It was a new record this morning, 72mph and still increasing, but I didnāt dare to go any faster, and itās really unnecessary and stupid after this road too.
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Without having any experience in woodgassing at all and with the risk of making a fool out of myself I would say that the dry charcoal is āstealingā most of the water vapour coming off the wood making for less condensate from your hopper and more water through your hearth and as a result getting weaker gas
Edit: but if dry wood is used and charcoal added, why would the system run cooler?
72mph, thats really good, I would be happy with that. Iām happy for you Jan, keep breaking those records 
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Dry and small fuel consumes oxygen faster. With no oxygen present closer to the grate, the gas leaving the gasifier gets relativly cool.
Damp and bigger fuel (with less surface area) will react slower and oxygen will still be present further down in the charbed.
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Never think that, l dont think anyone in the history of DOW was ever marked as a fool for speaking his thods.
Yes, charcoal āstealsā the water but it does so by converting it to more CO and H2. It changes the overall rato of carbon vs water in the fuel to a more favourable ratio. It raises the temperature in the hearth some, so reactions happen faster and more complete. Better gas.
A āhotā sistem usualy means incomplete reduction or water present in the finished gas. Steam has a lot more heat capacity thain woodgas so it carrys the heat out further in the sistem. Heat that it has previously stolen from the hearthā¦ so its best to deal with the steam before it exits the hearth, and the best tool here is hot charcoal that converts it to CO and H2.
Jans car observes this. His lambda shows too litle air, means richer gas. My question is Jan can you not just add in more air on your air seting?
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You probably produce very rich gas that requires a lot of oxygen.
Edit: Opsā¦Kristijan beat me to it 
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Well, I try to have the air so that the engine runs as well as possible, I have a big throttle for the air, so it is quite sensitive
ā
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The speed seems good, but I would rather have it a little stronger on the slopes, but it could be due to the ignition, if I rev it goes better, but I donāt like it.
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