Turbo Charging or Super Charging Woodgas Engines

Hi Mr Wayne and group, does any one here have any experience with boosting the intake pressure with woodgas.I have read that if the gas is pressurized to 6# above atmosphere pressure that full gasoline power can be recovered.( Dr Reeds gasifier hand book)
I have a super charger to put on my pickup it has a 300CID engine and it tops out at 60-65 mph on wood, I am running an Imbert style gasifier, and even lower when pulling a trailer. Any wisdom or experience on this will help.
The gasifier sizing will have to be changed, and this will also affect the turndown ratio, has any one else done this?


Just a word of caution. The supercharger will give your engine a “superhuman” ability to draw on the gasifier. This will make the gasifier work harder and run hotter. It will be very easy to overpull the gasifier. So you’re right, it needs to be scaled up a lot.

But it still has to run at an idle. So you’re now looking for a much larger turndown ratio to cover the difference. I suspect with enough heat recovery you could do it, at least on a Keith gasfiier. For the Imbert you’re talking about a massive hearth and super insulation. I don’t know how hard this is or what the results would be.

Vesa Mikkonen had a supercharged gasifier and blew it up. Sean French had a supercharged gasifier and blew it up. I’m not sure the specifics of their situations or failures, but you should talk to them before attempting this.

Chris, did Vesa or Sean share their build specifics about boosting the pressure that I could read about?.By blowing up do you mean burning up the hearth or exploding the gasifier or engine?
This must be possible but things have to be tuned in right , I dont know how any hearth can be more insulated than mine I have about 2" of refractory lining and the ash buildup inside this. I think this will hold up, but I am pretty amature in my experience yet.
Thanks for any input, if this is possible I would like to see one running. This will add a new dimention to wood gasification, because of the power loss.It seems though, if it was easy or possible someone would be doing it.
Thanks , Ron L

Ron & Chris, You could try running 2 similar gasifiers in parallel as I have done and just light off the second one when you plan to need the extra power like for pulling a trailer. My truck has a “:2 barrel” on it with an extra mixing valve. I just removed the second barrel last year. I have a pull cable on the roof that I’d pull to suck the extra gas off the second gasifier… When I was at Wayne’s last time I was just running the rear barrel and put a plug in the hole of the front one. I took the rear one off so it wouldn’t rot in the rain, snow, and salt and just run the front one. I put a plate in the mixing valve to close off the rear barrel. When I drove to Argos last year I just ran on the trailer which has a larger gasifier. I just pull the 3" PVC off the drop through the bed from the resident gasifier and then hook up the trailer hose to it.
Note the progression. I had the 55 gallon barrel early on it to provide around 9 seconds of reserve gas for hills and passing on the highway. It eventually got rot holes in it and I removed it. Note the rust on the rear gasifier. This was due to air leaks at a seam between 2 internal barrels and then the gas south of the grate was getting wasted and heated up everything else. I took it apart and brazed that whole joint.
Wayne showed me a nice roots blower last time I was there. He believes he could seriously pump an engine up and I don’t doubt it for a second. It’s too bad that Peter (I think) gave up on his S-10 project. I am currently working on a 1998 S-10 right now with a 2.2 liter to run on the trailer. Hopefully will be the Argos rig this year … ML

Hi Ron,

By “blowing up” I mean burning out the gasifier. I doubt you’ll kill the motor, but anything’s possible. You may blow up a supercharger though.

As far as Vesa’s experience, I think he mentions it in his book but I don’t remember details about it. Sean French has posted before about his experience, although I seem to recall he was pressure feeding the whole gasifier. In any case he’s said it gave gasoline level performance, but ended up burning out the gasifier. He doesn’t recommend it. He’s killed enough of them, he should know.


Just got off the phone with Wayne. He read your post but didn’t have time to respond to it (he’s driving to Asheville NC right now), so I’m posting this more or less on his behalf.

Mike, yes Wayne has a roots supercharger; he even mentioned today that it’s sitting on his shelf at home. He says he’ll never use it.

He had a few points to make. First off,the Dakotas are very well matched to the gasifier that runs them. He’s had a smaller V6 Dakota where the limiting factor was the motor, but there was plenty of gasifier. On the V10 the limiting factor is the gasifier - there’s more than enough motor. So in your case, depending on how well you feel the truck is matched to the gasifier, there may not be enough gasifier capacity to support what’s effectively a bigger engine (via supercharger). Whereas a bigger gasifier may not idle well. This goes back to what I posted above.

Another issue is the air mix. If you pressurize the gas you have to pressurize the air too. Second blower? Alternatively you could run a woodgas/air mixture through the supercharger, which puts it in harms way - one good backfire from the engine will take out the supercharger. A check valve would have to survive under constant pressure yet be able to blow off when the backfire came.

The alternative, at least on fuel injection engines is to just blend in some gasoline on hills or for heavy loads. If Wayne has to run the V10 on the freeway he’ll add about 10% gasoline to keep up with traffic (this is unloaded, no trailer). Now with a gas-over-carb setup you can’t do this. With gas-under-carb you have two throttles and this works OK. Leaving the idle feeds going gives me about 10 MPH boost, plus I have a second throttle to add some gas whenever I need it.

You might look into some upgraded parts instead of the blower.

  • A better intake manifold may do wonders for the gas flow into the engine. Something from the MPFI era, if it will fit. Remember you’re flowing about twice the amount of gases for woodgas as gasoline.

  • Exhaust headers on the 300 have less effect (stock is already pretty good, apparently), but still a possibility.

  • Check into different cam profiles. The 300 makes a ton of torque at low speeds, you might be able to trade some of that in on more power at higher speeds.

Years ago I visited with the Auburn Univ gasifier guys at a biomass conference. We talked about blowers. The Biomax 25 at the USFS facility in Louisiana has a blower to create the vacuum for start up but that is turned off when the engine cranks (running a generator). As I recall, the Auburn guys have a blower on their gasifier feeding the engine. I may have heard him wrong… but that’s what I was thinking.

The blower on the USFS Biomax 25 was driven by an electric motor. Seems like it was about 3/4hp or maybe 1hp. Driving it off a motor rather than the crank would give the user ability to increase or decrease boost on demand.

I think the biggest issue is that the engine vacuum is what creates the demand for more gas production hence the lag as it were. blowing into the gasser so it makes gas (instead of vacuum) may create less lag but creates all kinds of potential bomb like problems… I wouldn’t turbo or super charge an engine… maybe look at designing an engine that is actually optimized for wood gas? that would make more sense to me.

Hi Ron,

I am currently working out a hopped up blown WG engine combination for my truck. In talking to Vesa a while back, I believe he kicked the rods out of his engine first time around. I think the blown El Camino ended up doing 0 to 60 in approx 22 sec., which Sean can beat now with his Dakota. Many things to consider working out a complete combination, maybe kill some parts learning but definitely doable.
WARNING!! Hopped up supercharged engine mistakes will be far more expensive than gasifier mistakes.

I can see where pressurizing the gasifier would cause trouble and explosions,and also carbon monoxide leaking.
Wouldnt a blower running off the engine have the same vacuum effect on the gasifier relative to the RPMs, only with larger proportions similar to a larger CID. Like the 300 if it was boosted to 7#, 1/2 atmosphere more, draw the same as a 450cid engine,like Dutch Johns 454.
I know I have this thing in my head, and have read where it is technically possible but is it a practical improvement?

Hi Peter by blown do you have the blower at the primary air inlet for the gasifier, I know Sean has been running a WK style gasifier and keeping the hearth from melting down is a concern fron over drawing.From my experience the nozzles will limit the output for the imbert.
Did Vesa over power the engine or was there another problem?
What size engine and how much boost are you adding to your project?

Theory says yes, it’s the same as a larger motor. How much larger is the question.

All the gasifier cares about is vacuum. More vacuum means more gas produced, to the point of overheating. Of course when the gasifier plugs the post-grate vacuum rises without producing more gas. Always want to monitor the hopper vaccum because of this. It gives a pretty good indication of what you’re actually getting out of the gasifier. About 5" WC on the hopper is a nice steady load (on mine). More is fine for a while. Too much too long will lead to overheating.

If you put on the supercharger and see huge increases in vacuum, you’ll have to be VERY careful not to overheat the gasifier. Not saying it can’t be done, it’s just a bit risky.

Hi Mike thanks for the suggestion, this seemn like a good option,I am trying to keep all of the room it the bed that is possible, do you notice more power when you have both of the gasifiers running at the same time?
I should first see if I can get more gas from the unit I have now, it runs good and doesnt make any tar because of this I havnt tried to change any of the hearth dimentions, I should try opening the restriction some but now it is about 4 3/4 inches.

I will run a 6 or 871 BDS or SSI roots style blower. Keep in mind, the blower boost is infinitely adjustable with pulley sizing.

Hey Pete, when will you be mixing in the air?

Arvid, A mixer plenum on top of the blower.

I know Sean has been running a WK style gasifier and keeping the hearth from melting down is a concern from over drawing

Hi Ron,
I have been experimenting heavily with different sizes and materials to further the advancement of the WK gasifier. I believe some of these sizes and materials caused the failures as well as not having proper instrumentation on board the truck at the time. With this knowledge I am now operating better and driving faster without the supercharger.

Regards Sean

Ron, I have been working on the new truck. I have to wait until the melt down here to even move my trailer and to do some welding on the rear bumper of the truck as one end is rotted out. It is hard to lay under things today. I think I have the circuit stuff figured out and the PCV system so I can decide now where to plumb the gas in. The truck is a 98 S-10 with 2.2 liter and my cavaliers are 97s but there are major differences. Back to dual gasifiers, YES, running 2 in parallel put me up near where Wayne’s system runs. When I was at Wayne’s last time we took some test drives but we focused on timing his acceleration as he was planning on doing the salt flats. I had both gasifiers on the truck at the time and we could have fired up both to play with it. He welded up an elbow on it which is still in use. It just never seemed to stop raining there. It’s basically a 2 barrel carb. Just keep the second barrel a bit stoked up and when the hill comes up, pull the valve control and suck on both. I had the same sized double rotor hearth on both. I regret that I forgot to put a double rotor hearth in the truck for folks to look at last year. I think I had a small stroke or someone slipped me a mickey the day we left. Meshke had to wake me up … Mike

Peter, Do you still have your modified S-10 truck and gasifier ?? I’m hoping this is the case. You won’t regret finishing the project. I just laugh and smile every time I drive one of mine. Money is tight for all of us but when you get that baby going Wayne will finally have someone to race :o) … Maybe you can set the new world record ?? The S-10 I just bought has a plastic intake. Hope I don’t melt that down. I will probably take everything ahead of the throttle body off of it. Mike

Hi ALL!!!
Still get a kick out of this video remember this video was shot with No Gasoline And NO SUPERCHARGER/TURBOCHARGER needed.
One gasifier was on board the truck. Temps were normal, rpms very high.
I do apologize for the video being sideways it was a new camera. I think if you can zoom in on the odometer I hit 75mph in under a mile flat.
This is a v6 ford 202hp with the ability to ride highway like this.

And still idle slow like this

Ron the devil is in the details I am hear to help questions ask away. In my opinions though Supercharging/Turbocharging
is an extra item not needed to drive way above speed limits. Hope this helps Best Regards Sean

Hi , Sean this is a really impressive video with this kind of acceleration I would be very content, running up to over 4500 rpms is excellant, could you maintain this draw on the gasifier and what would happen if you had a trailer pulling like the video.
I have some questions but not much time right now . Ill contact you later have a good week end!! Ron L.