Wintertime in Portland, Oregon is filled with rainy, cloudy, foggy, chilly, drizzly, short days and worst of all – no track time. Portland International Raceway shuts down for the winter break in October and doesn’t reopen until March. Stand next to the front straight at PIR in November and you’ll hear nothing but the sound of raindrops hitting empty bleachers. But if you happen to find yourself 10 miles South of PIR, within a few blocks of 915 NE Davis, you might hear a racing engine somewhere in the mist. The C1 isn’t on the track turning laps; it’s in the test cell, turning the dyno. Recently we reviewed the dyno instrumentation and found the dyno absorber had turned over 4 million cycles and since the dyno is turned through the C1 gearbox, that’s 8.84 million crankshaft revolutions.
A typical dyno test lasts only about a day. The engine will start and run for several minutes at about 4000rpm until it reaches temperature, and then it will make between 50 and 100 full-throttle power ramps to its peak engine speed. Each power ramp will take approximately 20 seconds to complete. To date, we’ve built and sent across the dyno 34 C1 engines, burned 250 gallons of Elf racing fuel and used 200 liters of Elf synthetic oil. Do we really need to count the rolls of blue paper shops towels and pairs of disposable gloves? The tally of all these supplies is interesting, surprising perhaps, but ultimately trivial. It’s the human effort of a dyno run that is the single most significant number.
Roughly 80 hours of effort are required to assemble an engine. An inlet port reconfiguration requires 80 hours of machine time. Do you want to change the compression ratio? You’ll need about 20 hours of engineering time, and 20 hours to machine new piston crown details. Reconfigure the combustion chamber in the block? That’s right “ 20 hours to engineer the changes and 40 hours to machine them.”
This is development and we’re in the development cycle now; that is, no two C1 engine assemblies are the same. They vary in compression ratio, combustion chamber shape, cam timing, valve lift. We iterate on injector position, injector angle, inlet port configuration, firing order, oil system configuration. Everything about the engine is subject to change. Nothing is constant. What does this imply? It implies that these engines all go together differently. It implies that the builders can’t take a set of parts and throw them together with the conviction that the resulting assembly will be identical to the previous build. It implies that the engineering staff must continually research, test, design, and release the different engine specifications. It implies that the machinists must rework each engine monoblock to the latest specification. We don’t have the luxury of operating on autopilot here; because each of our engines is different, each requires the active involvement of the entire staff, engineering, machining, build, dyno. To date, the average C1 development engine has required about 550 man-hours of effort before it was finally bolted onto the dyno.
550 man-hours per engine. 34 engines. 250 gallons of fuel. Almost 9 million crankshaft revolutions. It’s been a long winter. But right now, the sun is shining through the MotoCzysz R&D facility and last weekend, PIR opened. We’re ready to park the dyno and go turn some wheels. See you at the track.
David Sprinkle
Chief Engineer, Electrical
Director, C-1 Prototype Development
David Sprinkle is one of the very dedicated and talented engineers on the MotoCzysz team. One of Dave’s tasks is overseeing the very complex electrical system in the C-1; he is also known as Dyno Dave.