QSB 7 Diesel Engine from Cummins. Cummins new 6.7L QSB is the next step up from the 5.9L QSB. The new in line 6 cylinder series comes out this summer in 380, 425 and 480 HP. The HP is the same as the 5.9-liter engine it replaces, and EPA compliant. The new EPA emissions standards for recreational boats were met without sacrifice.
Cummins 6.7 is the new 5.9 built to Tier 3 emissions amongst other things. The New federal EPA Tier 3 emissions standards require 55 percent fewer exhaust particulates and 17 percent less Nox combustion gases.
“Cummins MerCruiser Diesel’s QSB6.7 also provides more torque, which means better acceleration and maintained speed through turns. A pair of QSB5.9 480 hp engines installed in an inboard 44-foot express cruiser test boat accelerated the boat to 20 mph in 14 seconds,
CHARLESTON, S.C. – Cummins MerCruiser Diesel will unveil its new QSB6.7 at the International WorkBoat Show, November 30, 2011 in New Orleans, La.
The new QSB6.7 offers better performance, improved sociability, and improved operations over CMD’s beloved QSB5.9 model, all without sacrificing fuel economy. The initial launch of the QSB6.7 will provide both commercial and recreational ratings from 380-480 hp.
Cummins MerCruiser Diesel’s QSB6.7 also provides more torque, which means better acceleration and maintained speed through turns. A pair of QSB5.9 480 hp engines installed in an inboard 44-foot express cruiser test boat accelerated the boat to 20 mph in 14 seconds, while the same boat powered by QSB6.7 480 hp engines accelerated to 20 mph in just 8 seconds, with little change to the legendary QSB fuel economy. The QSB6.7 also employs a new fuel calibration strategy: Unlike most marine engines, the QSB6.7 is calibrated for optimal fuel economy at cruising speeds, where the engine is most often used, rather than at wide-open throttle.
The QSB6.7 is sociably improved, meeting EPA Tier 3 emissions standards. This new engine offers exceptionally low cold-start smoke levels, and significant sound reduction at cruise and rated speeds compared to the QSB5.9. Operationally the QSB6.7 has improved as the standard fuel system is compatible with low lubricity fuels. Also, the air-filter temperature sensor provides peace of mind when the engine is used in extreme temperatures.
Initial ratings for the new CMD QSB6.7 will include 380 and 425 mhp high output and intermittent duty and 480 mhp high output and government service. These ratings will be available for inboard and CMD Zeus® pod-drive applications. More ratings are scheduled for release in 2012, including commercial ratings from 250-305 mhp.