Each PROFORM 12.9 Steel (equiv. 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. It's 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.
Specifications:
| Description_ABR |
Header Bolts |
| Description_ASC |
Wedge-Locking Header Bolts; Hex Head; M8 X .984in; Chevy LS; Nickel Plt; 12 Pcs |
| Description_DES |
Wedge-Locking Header Bolts; Hex Head; M8 X .984in; Chevy LS; Nickel Plt; 12 Pcs |
| Description_DEF |
Exhaust Header Bolt |
| Description_INV |
Header Bolts; Hex Head; M8 X .984"L |
| Description_EXT |
Engine Header Bolts; Wedge-Locking Technology; Hex Head Type; M8 Thread X .984 Inch Long; Shiny Nickel Plated; 12.9 Steel; 12 Pcs in kit; Fits GM LS Engines with 1/4in Wide Flange |
| Description_MKT |
Each PROFORM 12.9 Steel (equiv. 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. It's 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. |
| Description_SHO |
Locking Header Bolts |
| Description_LAB |
Wedge-Locking Header Bolts; Hex Head; M8 X .984in; Chevy LS; Nickel Plt; 12 Pcs |
| Material |
Steel |
| Part Type |
Header Bolts |
| Category |
Header Bolts |
| Color |
Nickel Plated |
| Diameter |
8mm |
| Feature/Benefit |
Wedge-Locking Technology Eliminates Constantly Re-Tightening Exhaust Collector Bolts; Blocks Bolt-Loosening Rotation caused by Vehicle Vibrations. |
| Finish |
Nickel Plated |
| Length |
0.984 inch |
| Applications |
Fits GM LS Engines with 1/4-inch Wide Flange |
| Length |
2.0000 |
| Width |
5.0000 |
| Height |
7.0000 |
| Weight |
1.0000 |
