John Hartley isn’t your typical engineer. He is president of Faustel, Inc., a custom printing machine manufacturer in Germantown, Wisconsin, which isn’t unusual. What is: he built his own V8 engine. “I was talking with a buddy of mine while we were at the vintage races at Elkhart Lake about the idea of building a V8 out of two motorcycle engines,” he recalls, “and by the time we hit the Pizza Hut on the way home I’d decided to do it.” Although the performance of his Ford Zetec-powered Caterham 7 sports car was thrilling, its four-cylinder engine sounded flat and unimpressive, a problem Hartley was certain a V8 would not have. Setting a price of $6,000 for his project—“you have to start somewhere,” he says—Hartley started searching the universe of water-cooled motorcycle engines for “the ultimate motor.” He found it in the Suzuki Hayabusa. “It had more displacement than the Honda Blackbird or Kawasaki Ninja motors,” he says, “and the Suzuki was far and away the leader in both horsepower and torque.” In addition, the bore centers were greater and it drove the overhead cams from the crank end rather than its center, eliminating a potential weak point.
Despite admitting that the idea of building a motorcycle engine-based V8 was “a bit crazy,” Hartley continued to move forward. He bought a Hayabusa engine manual on eBay, and followed that with a complete engine procured through the online auction house. He read the manual cover-to-cover, then disassembled and measured the engine. The heads, cams, cam covers, cylinder liners, throttle bodies, and pistons basically would carry over, but the rest of the engine would be new. Hartley needed the engine to be sufficiently compact so it could fit in the same space as the four-cylinder Zetec, which meant abandoning an even-fire 90? design. “I wanted the bank angle to be as tight as possible for packaging, and 75? was as tight as I could go and still have room for the oil galley and enough structure to keep the block reasonably stiff,” he says.
After measuring the critical parts and laying them into his FastCAD program (Evolution Computing, www.fastcad.com), Hartley started with the design of the crank and built the rest of the engine up from this starting point. “I went with a flat-plane crank for horsepower, breathing, size, and scavenging,” he says. The block and heads, he figured, could be cast from 356/LM25 aluminum alloy, and he found a low-cost foundry that would make the patterns and cast the pieces for a reasonable price. Because he wanted to duplicate the size of the motorcycle engine as much as possible, he designed walls that would be much thinner than they would be in a car engine. “What I lost sight of,” he says, “is that—when you go to a V8—you are cutting double the number of holes in the case, which reduces its rigidity, while you are doubling the torque of the engine.” Thus, the first three engines flexed more than he liked and wore bearings out at an alarming rate. A rethink was in order.
“It only took me about six months of working on the engine in my free time to move from the initial measurements to the first cast 2.6-liter engine,” Hartley recounts. “Redesigning the castings and upping the bores from 81 mm to 84 mm for a displacement of 2.8-liters took very little time. However, moving from the cast engine to the billet block took a fair amount of time and effort.” That’s because—in addition to redesigning the engine to be cut from solid blocks of 6061 T6—Hartley decided he wanted to deliver full 3D files to the machine shops so they could pull the tool paths straight from the math without any need for intervention. And that meant teaching himself to be proficient in SolidWorks design software (www.solidworks.com) so he could create 3D CAD files.
“As I looked at the whole picture, I decided to split the case and have the bearing caps laid out as one solid piece.” To which he adds matter of factly: “Basically, you start out with about 200 b of aluminum and machine away about 80% of that to create something that looks like an engine block.” The machining is done in New York by a man Hartley describes as “an engine guy at heart” who was anxious to get the contract so he could put his new four-axis Fadal CNC machine (www.fadal.com) to work. In no time, Hartley had the pieces in-hand, and set about building the first billet-block engine. “The neat thing,” he says, “is that all of the speed parts for the Hayabusa are pretty much plug-and-play, and I’m working with one of the leading turbo makers for this engine—he gets 500 hp from race Hayabusas—for a package that will work with my V8.” Yeah, like the stock 400 hp and 250 lb-ft of torque of the stock motor isn’t enough.
Hartley has applied for a number of patents for the V8, including one that allows identical heads—one is reversed—to reduce the length of the engine. “It’s cut about 40 mm from the total length of the engine, and would probably reduce the package even more on a larger engine,” he says. The design uses the offset required for the second connecting rod to move the reversed head toward the cam drive, and saving 40 mm. “It could be more in a larger engine,” he says, “and you save on design time and inventory.” It’s one of many ways Hartley thinks mainstream automotive engine designers could reduce the box volume of their designs. “Motorcycle engines are more expensive because the engineers are focused on trying to get everything to fit between a rider’s knees,” he says. “The car engineers are undoubtedly just as smart, but have much less concern about the engine’s box volume because they have more room to play with. And while I’m certain they’d probably want to add a bit of stroke to increase the torque output of my engine, they also could design a V8 that fits in the same space as a four-cylinder—and reap the benefits it would bring in terms of size, weight, efficiency, and the ability to drop it into whatever vehicle you wanted.” It would even, he suggests, cost considerably less than the $25,000 he charges for each hand-built Hartley V8.