In order to convert a fuel injection system over to alcohol there are several guidelines one must follow.

The new injectors must:

  • Have about double the flow rating of the stock injectors
  • Be compatible with alcohol
  • Be physically small enough to fit into the stock throttle bodies
  • Have the proper electrical characteristics
  • Flow vast quantities of fuel over a very short period of time with the proper spray pattern and atomization
  • Be precisely positioned to enable the optimum spray targeting that is crucial to the difficult fueling demands of high RPM, alcohol injected, engines 

In addition to the new injectors the system will also require a fuel rail that is specifically designed for use with the new injectors, as well as the stock throttle bodies. Sufficient clearance must be left in order to run an air box. Proper fuel pump selection is also important to the success of converting a fuel injection system over to alcohol. Fuel injection pumps must be able to supply a high volume of fuel at a high pressure.

It’s easy to provide a high volume or high pressure fuel, but it’s difficult to supply both at the same time. Most fuel injection pumps are a flow-through design, meaning that the fuel not only flows through the pump, but also flows through the motor as a coolant. None of the flow-through pumps are 100% compatible with alcohol, as the alcohol degrades internal electrical parts and removes the lubricating grease from the bearings. Both of these issues cause a premature failure of the pump when used with alcohol. When asked, one of the larger fuel pump manufacturers said that their [expensive] pump could be used with alcohol, but to expect a 75% reduction of pump life and they recommended carrying a spare pump. There are other fuel injection pumps that are not a flow through design, but are rated for use with alcohol. Unfortunately they are very large and flow vast amounts of fuel. Since the fuel does not cool the motor, the motors have to be very large and draw lots of current. This current draw comes from the charging system, which takes power from the engine.

Selecting a fuel injection pump for use with alcohol can be challenging. The large, non flow-through racing pumps supply an over abundance of fuel for the 600cc engines. Only about 1/5 of the fuel supplied by these pumps is required. They rob power from the engine to feed their electrical demands and they are very expensive. It is our experience that these pumps do not last much, if any, longer than the flow-through type. The expensive racing flow-through type also supply a great deal more fuel than what’s required, again robbing power to feed the electrical demands and they are expected to have a 75% reduction in service life. If the recommendations of the expensive pump manufacturers are followed, a spare should be carried at all times. With this in mind, OEM style pumps are small, lightweight, and appropriately sized for the 600cc application, reducing the electrical demands. They are not rated for use with alcohol, so expect a reduced service life, but it’s common to see these pumps last more than a full season when flushed with gasoline while not in use.