【Precision 7/16-20 Drill Guide】:Accurate jig centers the harmonic balancer bolt crankshaft bolt hole on the crank snout—no second drill pass, no wasted time.
【Work Without Pulling the Motor】:Side ejection ports clear chips while the engine stays in the bay; perfect for LS crank bolt swaps on SBC timing pointer jobs.
【Aerospace Aluminum, Lifetime Durability】:CNC-cut hard-anodized 6061-T6 stands up to daily shop abuse and repeated use on classic 283–409 and modern LS platforms.
【One Tool, Dozens of Engines】:Fits For Chevy 153, 194, 230, 250, 265, 283, 327, 348, 409; GMC 248, 270, 302—covering every small-block and early big-block crankshaft pulley bolt job.
【Ready-to-Run Kit】:Includes jig, cobalt drill bit, and 7/16-20 tap—open the box, drill, and install your new crank bolt balancer bolt right away.