Each PROFORM Grade 8 Header Bolt is permanently assembled with a pair of special washers. When the bolt is torqued to 28+ ft-lbs, the washers super-hardened external teeth bite into and grip the bottom of the bolt head and the top surface of the header. After being self-locked in this manner, any bolt-loosening rotation is blocked by a wedge-locking action created by the washers interfacing, matching cams. Its an uphill climb: vibration that might ordinarily loosen the bolt actually increases the wedge-locking tension, securing the bolt even more. Because this simple wedge-locking method uses tension instead of friction, contact with oil actually facilitates the wedge effect. When changing headers, PROFORM Header Bolts can be untightened with a normal wrench, lubricated, and reused.

Features:
Grade 8 (12.9) Steel
  • Hex Head Type
  • 1.181-inch Length
  • Fits GM LS Engines with 3/8-inch Wide Flange
  • PROFORM Parts Brand Product
  • Sold as Set of 12
  • More From This Category

    Dedenbear Spare Solenoid,  Replacement Solenoid Only, For Ss2, Dedenbear

    Dedenbear Spare Solenoid, Replacement Solenoid Only, For Ss2, Dedenbear

    $257.33

    Main Bearing Set

    Main Bearing Set

    $73.45

    Ross Performance Dry Sump, Nissan VK56, Gold, Non Triggered, Kit

    Ross Performance Dry Sump, Nissan VK56, Gold, Non Triggered, Kit

    $7,978.99

    Billet Specialties Comp 8 Wheel, 15x14 in., 5x4.5 Bolt Pattern, 6 in. Backspace, Black

    Billet Specialties Comp 8 Wheel, 15x14 in., 5x4.5 Bolt Pattern, 6 in. Backspace, Black

    $1,617.98