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Mercury Racing

9.0 Liter V-8

Mercury Racing's 9.0 Liter V-8 Engine
Rated 1300 and 1350 Horsepower

Mercury Racing's 9.0-L V-8, an all-aluminum turbo-charged V-8, was CAD/CAMed from a proverbial clean sheet of paper. With a 552 cubic inch displacement, the monster motor's build list includes 32 valves, four camshafts and a dry oil sump. Twin turbo chargers jam air into each bank of cylinders via electronically actuated waste gates. Pulse-tuned exhaust scavenges the cylinders clean and minimizes  back pressure. The monster motor's black box boasts 10 times the computing power of previous modules. Even with a low 7.8 to one compression ratio, the bi-turbos require 91 octane fuel.

To handle the massive torque Mercury Racing built an all-new, surface-piercing stern drive and dry-sump hydraulic transmission. Dubbed the M8, the drive features forged gears as well as robust shafts and bearings. Twin pinion gears share the load and synergistically allow a narrower, more hydro-dynamically efficient gear case profile. M8 is 5 times stronger than a Number Six drive.

No big surprise, Mercury Racing's 9.0 Liter V-8 was influenced by technology  learned in the research and development of the Mercury Marine Verado series of turbo charged four-stroke outboards. Another knowledge base was Mercury's two-stroke direct-injected outboards. So naturally it follows lessons learned in combustion and durability will be passed on to its MerCruiser inboard and stern-drive engines.

In spite of race motor DNA, the 9.0 liter is a green machine. It's 20- to 30-percent more fuel efficient than similar engines and it meets EPA and CARB emissions requirements. When the engine gives up the ghost 95 percent of its parts are recyclable.

Finally, the engine has already found a happy home in Cigarette Racing's 46 Rider.