With the ultimate rod ratio in a 302 stroker the 1.696:1 331 stroker features the same offset wrist pin design as the venerable 347 Street Fighter. It is also benefited by the 1650 gram (approximately) bob weight, making this stroker one of the best street and strip engines of all time. 331ci Street Fighter 4.000 to 4.040 bore - 3.250 stroke - Flat top piston • Ford Racing 302 roller block • CHP 5140 forged fully bushed rods w/ARP bolts • CHP Hi nodular crank (shot peened & micropolished) • Probe SRS flat top forged pistons • Clevite plasma moly rings • Clevite bearings • Balanced & blueprinted • Your choice of 28oz. or 50oz. fully assembled