Skip to Main Content Skip to Footer Links
Error occured! Please reload the page and try again
Choose a Store
Open till 
There are vehicles in your garage

Free shipping on orders over $35.

Enroll in Speed Perks for more savings.

Cart is empty!

Add Something to the cart

includes estimated shipping

Vehicle added


Find parts for the selected vehicle:

View Vehicles
Are you sure you want to delete this vehicle?

    Add a

    Add a

    Proform Wedge-Locking Header Bolts, 3/8"-16 Thread Diameter, 3/4" Long, 12 Bolt Set

    Loading ...
    Exact Fit May Not Fit Doesn't Fit for your

    • Product Details

      Part No. 66751

      Warranty Details (90 DAY REPLACEMENT IF DEFECTIVE)

      PROFORM Wedge-Locking Header Bolts ELIMINATE the need to constantly re-tighten collector bolts, and without the need for clips, pins, racing-wire, chemicals or gunk. The secret is in the Wedge-Locking Washer's super-hardened external teeth that "bite" into the bottom of the bolt head and the top flange surface. Vibrations that normally cause other bolts to loosen, are blocked by the wedge-locking action that uses tension, instead of friction to stay snug. In fact, contact with oil actually facilitates the effect. Installs/uninstalls with a normal wrench, lubricate, and then reuse. Each set comes with twelve Hex Head, Grade 8 (12.9) steel bolts (3/8"-16 thread, 3/4" long) with a black oxide finish, and pre-assembled Wedge-Locking Washers.

      Product Features:

      • Grade 8 (12.9) Steel
      • Hex Head Type
      • 3/4-inch Length
      • Fits GM V6, SB 265-400, Buick, Olds, Pontiac '79 and earlier, Mopar BB 383-440 exc 413, AMC V8's w 3/8" bolts

    • Read Review
    • Q & A