Turbocharging MV Agusta’s Brutale
Somewhere in the vast, click-bait wasteland of YouTube is a video of a tuned Toyota Celica with all its radiator hoses blowing o in unison. That’s what happens when you get greedy with turbo boost and try to contain too much of it behind a flimsy stock head gasket. And that’s just a flesh wound. Turbo builders aren’t just resourceful wrenches, they’re curators of museums of melted pistons, cracked cylinder heads, and assorted other components pushed beyond the breaking point.
Building turbocharged motorcycles is even worse. In a car’s engine room, there’s at least space to contain a turbo, an intercooler, even a water injection system to quench runaway detonation. All that hardware hung on a motorcycle, if you can even find room for it, risks making the thing look like a first-year mechanical engineering project gone awry.
Those are precisely the challenges David Elias dealt with when turbocharging this MV Agusta Brutale 910R. Elias’s Turbo-R is a scratch-built, one-of project that yields an astonishing 220 horsepower at the wheel, and boosts peak torque by over 80 percent. “The horsepower kind of fell out of the project,” Elias says.”
Elias, a mechanical engineer by trade, set out a three-point design brief for the project: The finished bike had to be a daily rider; it had to run on pump gas; and it couldn’t desecrate the Brutale’s jewel-like aesthetics. These sound like conflicting goals because they are, but as with everything else, compromises pave the way to success.
Step one: the turbocharger. Elias wanted to avoid as much additional plumbing as possible, so he chose an Aerocharger, a unique design that modulates boost not with a wastegate, but via a series of annular vanes around the turbine wheel that, in effect, squirt the right amount of exhaust flow at the turbine to deliver the commanded boost. The vanes—which Aerocharger calls its Variable Area Turbine Nozzle—direct exhaust flow away from the turbine at low boost and toward the wheel for higher boost. The Aerocharger’s bearings are permanently lubricated via wick system and are nearer the cold side of the turbo so they don’t require coolant, making for a clean and entirely self-contained installation.
“The biggest challenge for us was keeping the artistic integrity of the bike intact,” says Derek Fischer of Attitude Sports in Salt Lake City, UT, who did much of the design and fabrication work, as well as the tuning. Fischer mounted the Aerocharger under the belly of the beast, at the end run of the exhaust header. The turbo is hardly unnoticeable, but it doesn’t scream I don’t belong here. The most conspicuous addition is a 2-inch aluminum charge pipe running up the left side of the bike from the turbo unit to the custom aluminum plenum that replaces the stock airbox. To prevent detonation, the stock pistons were replaced with custom forged, low-compression JE Pistons with ceramic coated domes.
The Brutale has the stock ECU with a racing chip, but there’s no ignition remap and the only additional electronic component is a high-performance fuel controller to increase rail pressure and to move more fuel through new, higher-flowing fuel injectors. How does one ride a 220-bhp Brutale? Gingerly. There’s no noticeable turbo lag, thanks to the Aerocharger’s light wheels and fast-acting vanes. Even with too-tall, 17/40 gearing—“I wanted to survive the first year, then gear it down,” Elias says—the Turbo-R is ferocious above 8000 rpm. If given its head on a long straight, the power arrives in one mounting rush, but isn’t realistically usable in cornering. Still, in the twisties, the turbo’s additional torque makes itself known. Entering a corner at 7000 rpm, for instance, the turbo provides an additional 25 lb.-ft. of torque. Where you might normally click down a gear, here you just roll on the gas for good exit drive. Yes, it’s tons of fun.
Every bike build has a bottomline and for Elias’s Turbo-R, the all-incost was about $13,500. He thinks a DIYownercoulddo it for about $5000 in hardware, plussomedynotime. “It’s predictable, it’s smooth and I don’t know any reason the Aerocharger wouldn’t work with any sport bike,” he says. It’s just a matter of money and will. But then, it always is.