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How to Modify a Car to Run on Ethanol
By Darryl James, eHow Contributor

Ethanol, a plant-based fuel source, is the most widely used alternative fuel source in the nation. Most popular is the specific blend of 10% Ethanol and 85% gasoline (E10 at retail). It has proved to work in standard vehicles as well as in flexible use (flex-use) vehicles. Flex-use vehicles are designed to tolerate higher blends of the fuel source --- up to as much as 85% Ethanol (E85 at retail). However, because the clean-burning fuel is cheaper than unblended gasoline, some car owners are looking for ways to make modifications to their vehicles to be able to accommodate higher Ethanol blends than the popular 10%.



Things You'll Need

Spark plugs
Fuel filter
Fuel injection kit
Carburetor
Fuel pump


Instructions

1
Install an Ethanol fuel injection kit, which allows the fuel injector and connected hoses to provide greater flow of fuel than traditional gasoline. Even the fuel line hoses have to be changed because the material makeup is important --- neoprene hoses work best for Ethanol, an alcohol-based fuel that can cause rubber and plastic hoses to deteriorate.

2
Remove the current carburetor and replace it with a smaller carburetor, which will restrict the air/gasoline mixture, making the vehicle better able to facilitate the use of Ethanol. While not all cars have carburetors, the notion is that larger carburetors have some difficulty adjusting to the divergent oxygen content of Ethanol blended fuel.

3
Remove the factory-installed fuel pump and install a fuel pump specifically designed to process and move an Ethanol gasoline blend. The new fuel pump will complement the fuel injection enhancements and allow you to garner the maximum performance from the fuel injection.

4
Replace the fuel filter. The idea is that Ethanol has more impurities than unblended gasoline, so the fuel filter will collect more particles more often and will, accordingly, need to be changed more often.

5
Replace the spark plugs. Again, the idea is that Ethanol-blended gasoline has more impurities than unblended gasoline, and particles may collect on and around the spark plugs, causing them to misfire and requiring more frequent changing.


Tips & Warnings

While the steps above are not very difficult, they do require a basic familiarity with vehicle operation. However, to be safe, it may be wise to consult a professional. If the fuel tank, for example, has to be replaced with a tank made of polypropylene and polycarbonate, a mechanic should be consulted, unless you have adequate experience replacing fuel tanks.