How big can you make a PMA? Is it possible to make one that is 3 feet round?? Reason why I am asking is I got to see a wood gasifier in action. He was running a small 4 cylinder car engine with it at idle. Could you make a pma that size and be able to run it a 800 to 1200 rpms for 8 hours a day??? The guy didn't have very many answers to my question. I figured that size maybe you could put cooling tubes in it to keep it cool. Just wondering.