Automotive Dual-Fuel Wood Gas/Gasoline?

It seems to me that converting a vehicle to be fueled on wood gas would be easier in a “dual-fuel” mode where a smaller gasifier is used not to fully replace gasoline, but to reduce its consumption. My reasoning is that a vehicle normally demands a very small percentage of the rated power from its engine. Therefore, a small gasifier should be able to replace most of the gasoline fuel. This approach should derate the performance of the vehicle a lot less than a full conversion since gasoline remains available for use as required. Also, the cooling and filtering system can be a lot smaller with this approach.

QUESTION: Does anyone know of such a conversion and how it performs?

QUESTION: What sort of problems with this approach do you anticipate? In particular, how do you anticipate the pulse width on the injector solenoids to be affected by admitting a wood gas/air mixture? At what point should this mixture be admitted to the engine for best results, and why?

FYI, the kind of configuration I imagine is to use gasifier from All Power Labs to dual fuel a small pickup truck. I’m hoping that a small gasifier like this can make a simpler and cleaner conversion. Also, I am quite certain that this gasifier is a lot better (and cheaper in the long run) than anything I would build. Anyone, please chime in and let me know if this idea is flawed, or if it has merit. Please share your thoughts.

Mark Goodson

With Waynes design you can run both wood and gasoline at the same time if you wish to. All you have to do is keep the motor fresh air intake valve full open, close the woodgas valve some and give the fuel pump just enough power to leak gas through the injectors. But why burn the gasoline when wood is alot cheeper. If you were a premiun member you could see that on this site

Richard, the reason that a dual-fueled system might interest some is to allow for a smaller gasifier and a much smaller and less obtrusive filtering and cooling system. My thinking is that a much smaller system would be worthwhile if it can replace most of the gasoline normally used, and I believe such a smaller system would be preferable to many drivers. Furthermore, such a conversion would allow for using small gasifiers that are currently manufactured (like the one available from All Power Labs). Not having to fabricate a gasifier system from scratch will make the project more practical for most people. I believe a dual-fuel system can get a lot more more people driving on wood. NOTE: It may also see better performance than most wood gas conversions, and it may be easier to operate such a system.

The kind of configuration I have considered is to use a small gasifier, and to admit a wood gas/air mixture to the intake manifold past the maf sensor using a hand throttle. Any automotive technicians please chime in as to whether or not this would work and/or what problems to expect. I’m hoping this approach can allow for driving mostly on wood during low power operations while retaining the stock system for acceleration and hill climbing as required.

Hi Mark,
If you try to run an engine on a gasifier that is to small, then you will melt your cone out.
If you try to run that same gasifier on to small an engine then you will have to
clean the slime out of your valves
Build a gasifier,run an engine on it,Find out which engine the gasifier was built for.
The theary, and the principal is so well proven, the only question is “DO YOU WANT IT”

It takes a Lot of effort to gather, and refine your own fuel.
The only reason for working for this is for the LOVE of it.

Pay me $10 an hour and gasoline is still cheaper.than the work I put into this.
But grass clippings I can always find; When I go to the mountans, they call it
“pine nettles”. No matter; I can burn it;
Give me a4 inch log and I will shave it down and pellitze it;;; make it feed proper

When you need extra power to get up a hill or merdge on the freeway,
you just feed in a little bit of dino power NO PROBLEM

A small gasifier burnig CLEAN and power when you need it is the best

Thank you Daucie. I definitely want to do this. The primary purpose is to provide a backup source of fuel for both automotive and stationary power generation. This would be one more benefit to setting up a small gasifier for dual-fueling an automobile since the smaller gasifier can also be used for fuel a generator. There are times when excellent wood fuel becomes available to me (I live near a large lumber mill and next to a large forest). I like the idea be being able to generate my own fuel should be need arise. I think the most practical and versatile option for me is to go with a single small gasifier that can provide fuel for both automotive use and for stationary power generation.

So, can you think of any problems that might arise in dual-fueling an automobile in the fashion I’ve described?

How is your Vulcan doing for you?

If you burn anythig that grows you must deal with the glycerin
If you geit it hot enough to breack apart that compound you got i made.
Otherwise you gum up your engine
small gasifiers running hard are cleaner
And goose the gas when you need it.
You can only learn this by doing it
You got to be able to feel it …If you have it; then I cannot stop you
I you don;t’,I cannot teach you …Its got to be in your soul.

But don’t dspise the gaoline…Goose it when you need it

The APL system isn’t really all that small when you actually factor in a hopper with enough capacity to travel any kind of distance. How small of a foot print are you looking at?

Good Morning Mr. Goodson,

I see no problem with dual fuel.
Often when I am pulling loaded trailers with my work truck and the need for acceleration or speed, I may dual fuel when ever necessary.

I mention quite often about the 25% / 75% equation with gasified vehicles. The gasifier and machine being 25% and the 75% being the operator. With the above the main issues will be in the 75% category learning how to control and run smoothly.

Hi Mr. Keith. There’s definitely gonna be a steep learning curve (especially for me). This is one reason why I see the dual-fuel option as most promising. It can help me avoid the major hurdle of actually fabricating the gasifier and associated systems correctly. My main concern is how admitting a wood gas/air mixture to the engine will affect the fuel delivery rate at the injectors. I have no doubt that wood gas will burn alongside gasoline, I’m curious to know whether or not it will wreak havoc on the engine control system.

Mr. Keith, do your trucks use map sensors or maf sensors (mass air flow)? Where do you admit the wood gas/air mixture relative to this sensor (upstream or downstream)? My automotive knowledge is very limited, but what little I know suggests to me that a map sensor would result in a rich mixture for dual-fuel, and a maf sensor would work if the wood gas/air mixture were admitted past this sensor. I’m hoping to confirm or correct my thinking here, please help, :-).

Arvid, yes I’ve considered that I would have to use a different hopper on the APL unit. I’m partly concerned about the footprint, but more interested in avoiding having to fabricate a unit. In my case, I believe the total costs involved in purchasing a unit will be less than what it would take for me to build a unit, particularly when considering patchwork over an extended period. I also really like the extensive heat regeneration in the APL unit. However, I have also noticed the Vulcan units that are very compact. I understand they’re made according to standard Imbert dimensions, so it should do well with properly sized and very dry wood fuel. Your unit looks really compact by the way. In fact, if that’s your unit in the photo, then I watched your videos on YouTube just last week. Good stuff! :slight_smile:

Mark; Duel fuel (wood gas or petrol) co fueled (wood gas and petrol). My system, with the separate throttles,
will work either way, just leave the petrol fuel on and use the throttle of choice.


You can’t avoid the fabrication entirely unless you buy a truck already converted. Once you’re resigned to building the cooler, plumbing, condensate tanks, new hopper, mixing valves, filters, having the gasifier pre-built is not saving you much.

Most folks who’ve finished Keith gasifiers report their costs as under $5,000. You’ll be very close to that if you buy your way with a GEK, and I suspect you’ll be disappointed with the results. It’s simply not designed to run a large engine.

One other thing about dual-fueling; it can be dangerous to the gasifier. If you let the fuel run out unawares, the engine will keep chugging along and you may not notice your gasifier melting behind you. Same goes for bridging and poor quality gas. Instead of the engine stumbling or performance decreasing, all those warning indicators will be masked by the gasoline.

Chris; You are correct about running out of fuel in the gasifier. The only warning sign will be a large puff, or worse a big boom.

Hi Mark,

There is a lot of good info here regarding vehicle installations and conversions. Our machines are designed for stationary fixed throttle applications and we have no experience with vehicle installations. We can build a machine for you; however, making it all work will be entirely up to you. You will need to fabricate all the systems to support our machine.

If you dual fuel a good point is mentioned with running out of fuel or if the machine bridges on you. You will need some sort of safety mechanism to prevent a melt down.

And that is the reason I pelletize all my fuel.
It makes it flow so well and behave
It takes a small restricter cone to handle the small size of the pellets
So multiple cones working togather could handle the volume
needed to run a V10 dakota
Just a thought

Hi Matt. I’ve followed the progress of your Vulcan since earlier this year. I like the compact design and in particular the way you have used existing components to get the cost down (very clever).

Whatever system finally evolves in my case, I’m convinced I’ll have to pay a lot of attention to fuel processing, providing indications including pressure and temperature, and protect against a low fuel condition. I’m hoping for a system that can be driven primarily on wood gas except when the engine demands exceed the gasifier rating, but the stock system must be able to deliver the balance of air/gasoline. On the surface it seems a separate throttle for the wood gas/air mixture is the simplest configuration (I’m thinking a hand throttle on the steering column) while providing a means to limit the d/p across the gasifier. My main question is whether or not modern automobile control systems will be compatible with this configuration. My simplistic understanding of automotive systems suggests that admitting a stoichiometric wood gas/air mixture past the MAF sensor at a low rate should work. Anyone please advise otherwise if you know better.

It takes a whole lot of work to refine thick oil sludge into premium gasoline.
Why do you think that a gasifier will solve all these things.
If you run on biomass, then you must acsept that you get only
60% of what the “PROS” do.
That is still good enough to make a happy life
AS a matter of fact, when you do it yourself; it just FEELS BETTER.
I do it becauce I LOVE IT. but it is a lot of WORK

I just bought mysefl a garden tracker to suck up the leaves in my
neobures yards. They think I am a hero. I tell them that I am going to
gasify them and fuel my house; but they don’t understand.
They don’t care; All tyhey know is they get a clean lawn
and I am gone. Weird dude, but cleaned it up good.

Only 10% will accually consider this…Only 10% of thows will
actually try it.And only half of those will accually succide

This is labor intinciv and intuitive in nature. You have to have a
FEEL for it. If you have it, then I cannot stop you.
If you donnot, then I cannot teach you
It is like hangegliders ; If you got it, then fly with us
If not, then stay on the beach
Us fliers have to say NO to a lot of “want to bes”
And that is the hardest call to make.
To cruch the dreams of someone that wants to
And say “You cannot handle it and I will not teach you”

But it must be done!!!
Talk with aman for 20 mins and you will know if he can
do this, or not.
It is sad but true Don’t tempt a man into something that
will hurt him
Sometimes you Must sayh NO