You have entered a very interesting quest, gasification. Like many others, myself included, you are starting with the FEMA. In that respect, I offer some pics of my humble beginnings. I finally got the gas to flare and did a whoopee dance around the unit. I was hooked, but I had also done more reading on the subject and realized the FEMA’s usefulness was very limited due to the relatively low temperatures, tar production, etc. The experience was not a waste at all. I got back into welding and fabricating, honing those skills and found the imbert design I finally settled on. Go on experimenting and reading about gas production. A great site for information on the science of gasification and how it relates to gasifier design is put up by Jim Mason, a guru on the science of gasification and design, imo. There are ten 15 minute sessions. You will learn so much there, you will never regret the time spent.
Here’s a few pictures of my FEMA so you can see how much the project entails. This can be built smaller, depends on hp required. There are charts on the site here.
The left is the base where the fines settle. The middle is the shell that holds the firetube and where the gas is drawn from. The right is the 6" fire tube inserted into a milk can for ease of installation ( fire tube sized by hp needed). Airtightness essential.
Gasifier with cyclone (to collect particulate matter) and cooling tubes (to cool gas and condense the moisture). Not shown is a collection container for liquid to drop into at the end of the cooler run. Also not shown is a final filter before the gas enters the engine.
Here’s a vid of one of my FEMA runs:
:40 use this for paper test only! Wood fire will instantly melt your vacuum hose. Now how did I find that out!
Note sizzling moisture in gas at end of run. This moisture will be sucked int your engine and foul the plug for a no start! Drain it out of the system before the intake.
Have you considered using a vacuum cleaner as your fan.
I hope this helps, but whatever you do, have fun!