The FAQ's say that it works with sequential multi port fuel injection. Only the California version of the 5.0 is so equipped, including MAF, for 1994. The 49-state version was bank firing and MAP. If the only connection to the engine is at the injector harness, then I suspect that it just lengthens the injection pulse by the percentage necessary to equalize the eqivalent energy content by volume of fuel.

This will not increase the compression ratio or even advance the ignition timing in order to take advantage of the increased octane and recover some of the lost mileage.

A rebuild with high-compression pistons, along with fuel and ignition timing remapped in the computer is what is really needed to convert to dedicated E85 and run optimally.