Well gentlemen, it's time for another wacky project.
This next chapter in my truck's development will be the most massive and sophisticated undertaking of my tenure here, easily eclipsing my fuel system build and quite possibly the sum of all my previous contributions. This project may be controversial among the 12v community, and as such, I initially wasn't going to publicly document it. However, the project has evolved well past its original scope and now includes an H1000 injection pump swap. Since this has never been accomplished before, it would be a great disservice to the B-series community to pull it off and keep it to myself.
Scope Creep: Story of my Life
I am a project manager’s worst nightmare.
This started out as basically a homebrew instrumentation system that would display sensor information on a screen and have datalogging capabilities. I have spent a lot of hours tuning my trusty ox, and I have grown tired of the butt dyno and its vulnerability to the placebo effect. I'm a very numbers-oriented person, and my recent project of creating an Arduino-based fan controller with secondary features, such as datalogging, has shown me the usefulness of accurate sensors and the ability to record that data over time. You don’t have to rely on hunches and instincts so much because you have data to prove or disprove your suspicions! It’s great! Plus, according to my wife, datalogging is “sexy.” Yes, she’s a nerd. But, you know what they say. Happy wife, happy life!
I next had the idea to make this datalogger to control certain things in the truck.
I thought it would be silly to have a touchscreen on the pillar and then go on to drill holes in the dash for switches. These would typically be added-on items like my OBA compressor, airbag inflate/deflate, exhaust brake, accessory lighting, etc, but could also interface with the truck in ways like a shutdown timer, manual CAD control, and driving the dash gauges for better accuracy and speedometer correction. It could also allow for “smart” control of certain features. A load-compensating fast idle feature using the stock cruise servo could be added, and that could be operated in conjunction with the exhaust brake to give an automatic, self-canceling warmup mode.
This, of course, led me to the idea to create an electronic fuel control for the P7100.
It wouldn’t take much additional work to mate a stepper motor to the back of the AFC housing which could move the foot with a leadscrew. 3 sensors, already in use by the datalogging side, could supply all the necessary information to automatically define preboost fuel, the boost fueling curve, and max fuel, and would inherently apply automatic altitude and temperature adjustment to all fueling conditions. It would only be one small step further to develop algorithms for derating the engine based on high EGT, drive pressure, coolant temp, RPM, etc. These parameters could be saved and tunes could be selected on the fly.
However, no amount of electromagical AFC mischief would fix the static timing inherent to the P7100, or the quirks of RQV-K governor that start to get teeth and claws as you continue to turn up the power. You may recall that timing is something I’ve been fixated on, basically since I got my truck, and I have had a strong desire to come up with a mechanical timing advance. This is not a new idea by any means. Many have come up with various concepts of mechanical timing advances, and my progress was halted by the same things that have halted everybody else. They would be time-consuming and expensive to develop, with a rather limited market, and a bolt-on kit would be virtually impossible to price reasonably. I was a little disappointed that this project would accomplish so much in the way of fuel control and yet still fail to bring us dynamic timing. I had almost made peace with this, until @cumminsrulez
called and we got to talking. Some stuff happened, and I was able to acquire an H1000 injection pump.
I had been casually looking for a few years, but as they are somewhat rare, I never looked very hard. In a nutshell, the H1000 could be described as a stroker P-pump on steroids. The pump uses control sleeves around the plungers instead of fixed barrels, which are moved up and down to change injection timing. The nature of the electronic governor would eliminate all the RQV-K’s quirks and trade-offs that gradually become nuisances and eventually turn into drivability issues as you turn up the power. With complete, programmable control of all basic running functions, injection timing, and fuel rack position, the only tuning and drivability edge a CR would have over this setup is multi-stage injection, and I wouldn’t have any of the CR problems as the fuel metering is still mechanical. That’s a trade I’m okay with.
The final conceptual revision of this project then occurred when I started thinking about how limited the PCM functions are on a 12v. The automatic transmission stuff is pretty basic and went away with the manual swap. Alternator field control went away with the alternator swap, but it would have been very easy to convert to an external regulator. Cruise control and tachometer signal output will have to be transferred to the new computer anyway. That leaves the A/C compressor clutch and grid heater control. Requiring only an additional handful of I/O connections, I decided to set my crackerjack Cummins computer up at the hardware level to absorb the two remaining duties of the stock PCM so I can delete it entirely.
1 - Mockup Jig
2 - H1000 Initial Inspection
3 - Rant: Torx vs. Torx Plus
4 - Fitting the Pump
5 - Quickserve Datamine
6 - Oil Connections
7 - Fuel Connections
8 - Fuel Pump
9 - Analog Circuitry (Not Super Helpful)