I have two applications of the same design for you today. Both of these systems are resource-minimal and distribute fuel evenly between 8 furnaces.

Note: initial start-up requires 8 stacks of coal before top row begins to fill and system becomes fully operational.

Additional Notes

How it works:

The top trapped chest is filled with your fuel and is held until you close the lid. A comparator disables the hoppers leading into the furnaces, allowing the coal from the top chest to be evenly distributed into the two lower chests. Once the top chest is empty, the lower chests will be released to fill the hoppers below.

IMPORTANT NOTE!: The bottom row of hoppers should have 4 of their 5 slots filled with any non-fuel block. This will hasten the filling of the top row of hoppers.