As promised, here are a few pics of what it looks like in the truck. As you can see, it's buried so far down in there that you can't really see that much. However, it is clearly an H-pump because it has no throttle linkage. The pic that Runsideways posted is much clearer because it was taken whilst the engine was on the stand.
Now onto the basic operation of the pump, & why it is so vastly superior to anything else out there.
It is an inline pump with a MUCH larger cam, thereby moving greater quantities of fuel at substantially higher pressure that a P-pump could ever dream of doing. Numbers? About 180% more fuel & 350 bar higher peak pressure than a P-pump. (A P-pump peaks at around 1100 bar, the H-pump peaks at 1450 bar.) But the best part about it? It has that magical second rack that adjusts timing! You time this pump exactly as you would a P-pump. Mine is set for an initial timing of 10° (for ease of starting, quiet non-rattlely idle, & quick spooling) however, the pump can move that all the way to 40°! And the two racks (fueling & timing) are totally independent of each other.
Unfortunately, the pump is NOT — as was alluded to earlier in this thread — a direct bolt-up; not even close! It requires machine work on the pump & the housing. Then you need to figure out how to oil it, & drain said oil from the pump to prevent hydrolock. And you have to figure out how to drive it. As I stated previously, the pump has a much larger cam in it. Even if you know how to machine a tapered hole you'd hit air on the stock gear before you got large enough to fit the pump cam; if you could figure out the angle of the taper (which I will tell you this much, it's not standard.) Plus you need to fabricate a new rear mount (the one from your P-pump won't work) & clearance the tappet cover. Then, because the pump is 50mm taller than a P-pump, you need to fabricate injector lines, & most likely make a new air horn (because the pump will foul it as it is taller).
Presuming you have the pump mounted to — & driven by — the motor, you now need a way to control it, as there is no provision to mechanically move the racks; they are actuated electromagnetically. This means you need a bunch of sensors on the motor, which would, at a minimum, include: crank position sensor (with a reluctor wheel), accelerator pedal position sensor, coolant temp sensor, & mass air flow meter. And finally, you need to make an electronic controller, because there isn't anything out there commercially available.
If all this sounds incredibly complex, that's because it is! Was it worth it? Emphatically, yes! The truck is a joy to drive, with an exceedingly wide power band. I won't tell you my peak numbers, but I have a minimum of 1000 ft-lbs between 1100 & 4200 rpm. Yes it really is that wide! And the reason is because I can vary my timing. Timing is key! And the importance of variable timing cannot be overstated. Basically, when P-pump trucks (setup for the street) peak out at about 2700 rpm (because of timing) I can rev anther 1500 rpm; & make power all the way there!
I tried to load a video of the truck running, but I kept getting an error. Any ideas?
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