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

    COMP Cams Cylinder Deactivation Delete Kit, Premium DOD Delete, GM GEN IV 5.3L LS, Kit

    COMP Cams Cylinder Deactivation Delete Kit, Premium DOD Delete, GM GEN IV 5.3L LS, Kit

    $1,370.44

    Rear Main Seal Set,

    Rear Main Seal Set,

    $33.23

    Cast Piston Set w/Prem. Rings

    Cast Piston Set w/Prem. Rings

    $493.25

    QA1 H Series 3 Piece Alloy Rod End, 5/8in. Bore, 5/8in.-18 RH Female Thread

    QA1 H Series 3 Piece Alloy Rod End, 5/8in. Bore, 5/8in.-18 RH Female Thread

    $61.77

    Rancho Suspension Strut

    Rancho Suspension Strut

    $388.70

    Ross Performance Crank / Cam Trigger, Nissan RB30ET, Metal Jacket, 36T, Kit

    Ross Performance Crank / Cam Trigger, Nissan RB30ET, Metal Jacket, 36T, Kit

    $2,012.67