[E4ODnut]

The really good thing about programmable EFI is that it allows you complete control of fuel mixture and ignition timing with resolution simply not possible with a carburetor and conventional ignition.

But!

The really bad thing about programmable EFI is that it allows you complete control of fuel mixture and ignition timing with resolution simply not possible with a carburetor and conventional ignition.

The bad part is that you really do have enough rope to hang yourself, but there are rewards if you don't screw up.

Having said that, from my experience, generally the OEM has done a very good job of balancing power, economy, and emissions concerns with any of their EFI engines. Any gains you can make in one area will be offset by losses in another. I've gone to a lot of effort to try squeeze a bit better economy out of my 300, but I've found it very difficult to do. Also even harder to document, because the vehicle is my daily driver and service van which tends to gain weight, which in turn will offset any economy improvements. Ethanol blended fuel doesn't help anything either, but that's another subject.

Why do it then? You might ask. I suppose because I find it interesting and challenging. But it's pretty lonely out here. Most programmable EFI is used by the go fast boys. Not much interest in economy tuning, and even less with the Ford 300. There is a pretty level headed bunch over on Fordsixperformance forum, but even there I've found no one else experimenting with it in this way.

The 300 produces very good torque, not massive, but very good. What sets it apart from most engines is that it will produce this torque right down to about 1200 RPM. It behaves more like a naturally aspirated diesel then a gas engine. The problem is that it's Brake Specific Fuel Consumption numbers simply aren't very good so it's pretty hard to gain much. I've found I can run my engine relatively lightly loaded with A/F ratios between 17:1 and 18:1 before it starts to complain. This should result in economy gains, but in my application I'm hauling so much weight that I'm very rarely in a light load cruise situation.

So, I suppose, it's not so much the destination as the journey, but it would be nice to have some company along the way.