Editing GMC V6 engine (section)

===DH478===
The DH478 shares the same {{cvt|5.125|×|3.86|in}} bore and stroke as the D478 with a total displacement of {{cvt|477.7|cuin|L|1}}. The primary difference is the DH478 has an oil cooler standard, which is optional on the D478. The cylinder block is a chromium-nickel iron alloy with a 60-degree design.<ref name=65-engr/>{{rp|34}} It has a peak gross and net power output of {{cvt|170|and|155|hp}} at 3200&nbsp;RPM, respectively, and corresponding gross and net torque output of {{cvt|310|and|290|lbft}} at 2000&nbsp;RPM, respectively.<ref name=65-engr/>{{rp|61}}