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 .