Midway through model year 1998, the engine which would now be known as the ISB, was redesigned as a 24 valve model to meet updated emissions requirements and introduced the Bosch VP44 rotary injection pump (featuring electronic control) to the Dodge application. It produced 235 hp (175 kW) at 2700 rpm and 460 ft·lbf (625 Nm) from 1600 rpm to 2700 rpm when paired with a manual transmission, but was slightly downrated when used with automatics.
In 2001, an optional high output (HO) version of the ISB was introduced, producing 245 hp (183 kW) at 2700 rpm and 505 ft·lbf (686 Nm) from 1600 rpm to 2700 rpm when paired with a heavy duty six-speed transmission, the NV5600. The ISB from previous years remained available, and automatic-equipped engines were now rated the same as manuals.
