Cummins replaced its B4.5 — a 4.5-liter mechanically injected engine that produced 104 horsepower and 305 ft.-lbs. Your source for information and ideas on product development, performance, and ...
Cummins says its four-cylinder QSB3.3 and QSB4.5 diesel engines (75- to 160-horsepower) will meet EPA Tier 4 Interim emissions restrictions in 2012 with fuel efficiency improvements up to 5 percent.