For 1991 & later Gen. V & Gen VI 454 (7.4L) HO & 502 HO engines. This flexplate is required when using a steel forged crank on Gen. V design engines. This flexplate is 14" diameter (168 teeth). Technical Notes: This flexplate is similar to Mark IV design but not interchangeable because of balance. It has a dual-bolt pattern design. When using a 4L80 automatic transmission, only three attaching bolts can be used.