Found this mod on a Ranger site and wanted to hear what folks here thought.
Discuss How To: Dual ignition Plug mod (Dual plug 2.3/2.5L only) - Ford Ranger Forum
Basically what it seems to say is you switch the order the plugs are fired in. Not the firing order of the engine. This is for Rangers with the dual coil pack systems. I guess one plug in each cylinder fires on compression and one fires on exhaust(?) to burn any unburnt fuel left there for better emissions. Switching the order makes BOTH plugs fire on compression for a bigger spark I am guessing. The OP claims a gain of 2-3mpg highway.
Any thoughts?