Kooks Ford 5.0L 4V Coyote Engine Stage 8 Locking Header Bolt Kit (10mm x 150 Coarse Thread)

Kooks Stage 8 Locking Header Bolt Kit for Ford 5.0L Coyote, 5.2L Voodoo, 6.2L Supercharged Engines

The Kooks BK109 Stage 8 Locking Header Bolt Kit provides a reliable fastening solution for header installations on Ford's high-performance modular V8 engines, preventing bolt loosening and exhaust leaks caused by intense vibration and thermal expansion in 5.0L Coyote, 5.2L Voodoo, and 6.2L supercharged applications.

Made from high-strength stainless steel with an integrated locking mechanism, these M10 x 1.25 x 25mm fine-thread bolts maintain secure clamping force across 16 ports, ensuring headers remain sealed under boost pressures exceeding 20 PSI or track-level RPMs.

Unlike standard hardware that requires frequent retorqueing, this kit's design delivers consistent performance for tuned setups pushing 800+ horsepower, making it essential for Mustang GT, Shelby GT350, F-150 Raptor, and F-250 Super Duty owners upgrading to long-tube systems. The direct replacement for lost or damaged bolts in Kooks header kits integrates seamlessly, supporting daily drives, drag racing, or towing without compromising integrity.

Key Features

• Stainless Steel Material: Resists corrosion and endures exhaust gas temperatures over 1,500°F without fatigue.
• Stage 8 Locking Technology: Built-in locking feature counters vibration-induced rotation for long-term security.
• M10 x 1.25 x 25mm Fine Thread: Precision sizing matches Coyote, Voodoo, and 6.2L cylinder head ports exactly.
• 16-Bolt Set: Full coverage for both banks on V8 engines, with hex heads for easy wrench access.
• High-Strength Construction: Rated for repeated torque cycles up to 30 ft-lbs without stripping.
• Replacement Compatibility: Fits all Kooks headers for listed engines no modifications needed.

Product Notes

• Order only as replacement for damaged or lost bolts included standard with Kooks header kits.
• Fine thread specific to 2015+ Coyote/Voodoo and 6.2L supercharged heads use BK108 for coarse thread pre-2015.
• California Proposition 65: Contains chemicals known to the State of California to cause cancer or reproductive harm.
• Not for use on non-Ford modular V8s verify thread pitch on aftermarket heads.

Warranty: Limited lifetime to original purchaser against defects in materials or workmanship.

Installation Notes

• Clean port threads thoroughly to avoid cross-threading apply anti-seize for future serviceability.
• Torque in a crisscross pattern to 25-30 ft-lbs recheck after 100 miles or first heat cycle.
• Compatible with standard 13mm/16mm sockets no special tools required.
• Professional header install recommended bolt time adds 15-20 minutes to process.

This Part Fits

Note: Fits fine-thread cylinder heads on 2015+ 5.0L/5.2L and all 6.2L supercharged Ford modular V8s. Confirm head type for pre-2015 applications.

What's Included in the Purchase

• (16) M10 x 1.25 x 25mm Stainless Steel Locking Header Bolts
• Associated Locking Hardware (Washers and Inserts)
• Part Number: Kooks BK109

Why Choose Kooks?

• Over 60 years of exhaust engineering, with victories in NHRA, NASCAR, and SCCA events.
• Handcrafted in the USA from premium stainless steel for precision and reliability.
• Limited lifetime warranty and expert support for all installations.

Frequently Asked Questions

• Q: Does this kit fit my 2014 Mustang GT 5.0L?
  A: No, 2011-2014 Coyote uses coarse thread select BK108. BK109 is for 2015+ fine thread.
• Q: What torque should I apply?
  A: 25-30 ft-lbs in stages, using a calibrated torque wrench for even clamping.
• Q: Are these bolts reusable?
  A: Yes, the locking mechanism allows multiple installations without performance loss.

Shipping & Handling

• Method: Standard ground UPS/FedEx.
• Availability: In stock and ships within 1-2 business days.
• Packaging: Secure pouch in a reinforced box to safeguard threads.