Help learning what engine I can run

I’m new to woodgas. Do I need to have a flex fuel engine?


Welcome to the site.
Gasoline internal combustion is easiest. Diesel is possible but more work to convert. You need a large cc engine because woodgas is more voluminous than gasoline/air volume.
It is easiest to use one with aluminum/steel intake manifold/etc. so you don’t melt a plastic one when it burns out the soot upon backfire or cleanout eventually.
Engines already set up for propane have been easiest for us to convert. But that’s basically just a gasoline engine with a different fuel delivery system, which you will convert anyway.

Probably the most commonly used gasifier on this site is the Wayne Keith. And the most commonly used engine for that gasifier is probably the 318 Dodge v-8 in the early 1990’s Dakotas.


Hello Mark and welcome to the site .

Below is some reading on the subject .


No. Flexfuel usually means it is E85 capable. Woodgas is it’s own beast. However, a LOT of e85 vehicles are naturally aspirated, which could make it a lot easier to convert a vehicle.

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Factory flex-fuel vehicles do have a lot more ignition timing advance pre-programmed into them. This was to without better higher compression ratios to get back as much power on 85% alcohol as possible.
I only a few times operated the wife’s 99 Plymouth mini-van on E-85. It; out and about, ran just fine. Even highway tripped, just fine. Boo! 30% higher fuel consumption. On fuel that cost, out here far-Left-coast, 50 cents a gallon more.
Her’s had no in-the-fuel-line alcohol detector sensor. So it had to use enhanced knock sensor information, with quicker responses, to use the wider range timing mapping.
Later systems DO have in-the-line alcohol % sensors. Great. Spoof the sensor when on woodgas to get your more advanced ignition timings.
Factory, Fex-fuel systems offers better woodgasing possibilities imho.


I think the original ones used fuel sensor too. but it was an either/or so if it detected you had e85, it would change the timing, but any mix inbetween, it would revert to gas settings, and maybe that was just the anti-knock sensor.

The newer ones the detection shifts based on a percentage. The problem being that e85 can contain ‘up to’ 85% ethanol’

Ethanol was cheaper then gas on the wholesale market by over a dollar a gallon a week or so ago when I looked. But yeah I only use e85 when it is cheaper then the 25% spread, and that isn’t always the case. I haven’t seen it MORE then gas in about 10 years, but I think we still waive some of the road tax on it in our state.


What about a Ford 5.8l 1990? I have no experience with this.