1. Long-stroke engines are known for their torque, and when turning big tires off-road, you want torque. That's why we are always so concerned with going to lower gears for torque multiplication. The stroked ZZ383/425 engine package comes from GM Parts Performance (GMPP) with a modified four-bolt main engine block, a 3.80-inch stroke 4340 crankshaft, heavy-duty powdered metal rods, and the one-piece rear main seal. It is also ready for an automatic transmission with a 12.75-inch flexplate, and comes with stamped-steel valve covers that we replaced with Scoggin-Dickey's fabricated aluminum versions. It does not include a starter or front accessory drives.