Hydrogen Cars. All the talk we hear now of hydrogen powered automobiles involves fuel cells. How about burning hydrogen directly in an internal combustion engine? [more inside]
posted by mbarryf on Jun 14, 2007 - 19 answers

When your [furnace/water heater/sauna/time machine] burns natural gas, should you feed it hot or cold air? [more inside]
posted by spacewrench on Aug 20, 2006 - 8 answers

What are the primary gases produced by propane combustion? I was just told a story about a nearby warehouse, very high ceilings, 2600 sq ft, which is being heated by umbrella-style outdoor propane heaters (think of outdoor restaurants in LA, for you left coasters). Visions of dead people litter my mind, consequently. Am I right, or confused with regard to the exhaust? Please provide authoritative links so I can pass this along without being confrontational.
posted by mwhybark on Nov 4, 2004 - 6 answers

SmallEngineFilter: My 49cc 4-stroke scooter runs at half the speed it did before replacing a tire and a spark plug. [more inside]
posted by IshmaelGraves on Nov 3, 2004 - 1 answer