ProForm 66751 Wedge-Locking Header Bolts Hex Head 3/8 Diameter X 3/4 Inch Black Oxide 12 Pcs

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0.50 LBS
Calculated at Checkout

Applies To Continental U.S. orders only

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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. Sold as a set.


  • Engine Header Bolts
  • Wedge-Locking Technology
  • Hex Head Type
  • 3/8-16 Thread X 3/4 Inch Long
  • Black Oxide Finish
  • 12 Pcs in kit
  • Fits GM V6, SB 265-400, Buick, Olds, Pontiac 1979 and earlier, Mopar BB 383-440 exc 413, AMC V8 with 3/8 inch bolts
  • Sold As A Set