Ok, I've got a few more minutes here.
To make power/improve mileage with an add-on box can only be accomplished in one of 3 ways:
1) advance timing. This is the absolute best way to gain mileage.
2) increase or decrease injector pulse duration. Difficult to gain mileage with this style of power increase, except that you can modify your driving style to use the additional bottom side power. If you combine pulse duration changes with timing changes you can make very good gains through improved injection efficiency.
3) increase or decrease injection pressure (only on common rail trucks, in other words, Duramax, Ford 6.0L, 03+ Dodge Cummins). Difficult to gain mileage with this style of power increase, except that you can modify your driving style to use the additional bottom side power.
Current light truck programming is pretty pathetic as its geared more for particulate emissions control than it is for power or mileage. The nice thing about a diesel is that as a general rule of thumb, if you boost power, you will get a mileage increase _as long as you keep your foot out of the fuel_. So virtually every power module, if you "drive at 55", will give you some kind of mileage boost. This is NOT a guarantee though, as every manufacturer uses the same sensors built by the same company with the exact same 10% tolerance, so you will get some trucks who will not gain mileage with the addition of a chip.
Now onto the Workhorse's "infomercial". OMG. I'd hoped this style of advertising had left the diesel performance world, but I guess it hadn't.
First, I won't say whether or not the Workhorse will add power or economy. I suspect it can do both, but certainly not any more power or any more mileage than any other add-on box. There is only so much you can do with an add-on box. To gain further power or mileage requires changing injectors, replacing cams, head work, reprogramming ECMs and changing turbos.
I noticed down at the bottom of the page that the Workhorse is a simple fuel pressure module. In other words, all it does add (or remove) rail fuel pressure. There are no plug-ins to the injectors so it can't change injector duration or timing, and there are no plugs for the cam or crank sensors so it can't even READ timing. All there is is a fuel pressure plug. So all it can do is read current fuel pressure, compare to a previous reading to see if its climbing or falling (called delta pressure) and decide to add more fuel or take more away.
So with that mind, there is NO way that they can achieve "improved combustion efficiency". Not without timing. Absolutely no possible way.
And there is NO way to achieve 500F reductions in EGTs, not that you'd ever want to. Diesel fuel is ignited by heat. The trick to efficient power production is keeping cylinder heat high enough to keep the fuel igniting, while not generating so much heat to break down the rest of the engine components. The ideal box on 03 Dodges keeps EGTs at a steady 1250F - 1300F at WOT. The 6.0L Ford, Duramax, and pre-03 Dodges preferred heat in the range of 1150F - 1200F.
6 MPG gains from a fuel pressure box are also impossible, except on the mileage computer. But once you install the pressure box, the mileage computer is so far out of whack that you never know for sure what the proper reading is.
Since it is a fuel pressure module, the price at $695 is too high, not to mention that you'd still want to put a pyro and boost gauge on anyway. Any performance manfacturer that recommends doing performance uprates without gauging shouldn't be in business.
I'm sure there are more holes, but those were the most glaring. Quite frankly, even if the box does add power, I'd stay a long way away from it. I get nervous when I see over-hyped testimonials, and long diatribes with no real information.
Rod
