Propane Conversion Basics Kurt Anderson 8/6/06 1. Resources1.1. Book: The book to get is Propane Fuel Conversions by Jay Storer. Its out of print, ISBN 0-931472-12-1, published by S-A Design, 1986. This book is the only one like it Ive seen. Its got a lot of good information, a little misinformation, and a few holes if youre using it to convert a car. Find it on amazon.com, ebay, at used book stores, the library, etc. 1.2. Components: Not as easy to find, but MM (was OHG, Ak Miller) are supposed to be the better ones. Marilyn Miller still has a shop in Pico Rivera, CA. Impco doesnt seem to like to sell to individuals, but their stuff is most common. 1.3. Other components: Gann Products (gannproducts.com) in Downey, CA has adapters, hoses, fittings, etc. 2. Reasons2.1. Cleaner 2.1.1. Several advantages to this, the main one for this forum may be that the oil/engine are less contaminated with metal-wearing carbon so your engine should last a lot longer. 2.1.2. 100+ octane, but the rating goes down as engine speed increases from what i get from the book. 2.1.3. Cheaper than gasoline: If you buy from a distibutor, it seems to be about 50 cents less per gallon. 2.1.4. Others: Easy to convert, carbs are simple and can be oriented any way, it seems multiple carbs would be easier to tune, supposed to make 4 and 6-bangers run more smoothly, and works well with turbochargers! Before you say non-traditional, I read in Gasser Wars that the Mallicoat brothers used twin turbos in 65. Ak Miller (R.I.P.) used propane and turbos for a long time. 3. Components3.1. Tank: Get a tank made for road vehicles, and buy it used for a lot less. The tank shouldnt rust inside unless its completely empty of propane. Get as big as you can fit fur better range. The tanks are marked for water content (WC); they are filled to 80% with propane. No fuel pump necessary. 3.2. Shutoff: Vacuum or electric, this is a valve (and filter) for the liquid propane coming from the tank. 3.3. Regulator (convertor): This converts the propane from liquid to gas, and therefore requires heating it with the coolant system. 3.4. Carb (mixer): Air valve, diaphragm, venturi, and combination types are much simpler than gasoline carbs. 3.5. Hoses/Fittings: Get the proper hoses and fittings for the pressure/media. Basically there are liquid hoses and vapor hoses. 4. Most important things4.1. Ignition: Because of 2.1.2. the initial timing can be advanced, but the overall timing should be less. Youre supposed to upgrade the ignition, also. 4.2. Valve seats: Same deal as unleaded gasoline. 4.3. Dont heat the intake, and you can run a cooler thermostat (as low as 160 °F). 4.4 Biggest disadvantage is refueling- you have to plan ahead. Attached pictures Impco 425 and 225 carbs and vacuum shutoff (lockoff). MM X-450 carb with bonnet for pressurizing with a turbo. MM X-1 convertor and electric shutoff (not shown). 22-gal (water content * .80) = 17.6-gallon tank. 27.2-gal (water content * .80) = 22.2-gallon manifolded tank. Impco Model E regulator/convertor PS: Propane tanks in the trunk need to be installed legally, unlike shown in the pictures. Basically, a tank hose/valve leak needs to be plumbed outside of the trunk so propane won't go into the passenger compartment. The easier way would be to convert a pickup and put the tank in or under the bed.