Chrome moly 12 pt 7/16″ flexplate bolts. Requires no washer and has a tensile strength of 170,000 psi. Recommended for stock flexplates. Torque to 85 pounds with stud-lock Loctite. Use FB-410 with Mondello Inertia Flywheels & Flexplates.
New ARP Chrome moly 3/4″ thread crank bolt and washer for 1964 to date Oldsmobile V8’s, except the 394. Hex head that accepts standard 1/2″ drive ratchet or breaker bar to rotate engine. Measure thread size of crankshaft before ordering.