KC 3.5 EcoBoost Exhaust Manifold Upgrade

Features & Details: 

• 30% CFM Increase over Stock Manifolds
• Port Matched Exhaust Manifold Runners
• 75% Thicker Manifold Flange 
• Utilizes 3 additional exhaust stud locations for better seal
• Cast with high silicone molybdenum to prevent warping under extreme heat
• Upgraded Stainless Steel Exhaust Manifold Studs with integrated Hex installation head for easy installation
• Includes New Studs, Spacers, Nuts, and MLS Gaskets
  

Fits the Following Vehicles with a 3.5 EcoBoost:

• Ford F-150/Lobo 2011-2016
• Ford Expedition 2015-2017
• Ford Transit 2015-2024
• Lincoln Mark LT 2011-2014
• Lincoln Navigator 2015-2017
• Replaces Ford OEM Part Numbers: 
  • BL3Z-9430-B
  • BL3Z-9430-D
  • BL3Z-9431-B
  • BL3Z-9431-D

Description:

The factory exhaust manifolds on the 2011-2016 3.5L Ford EcoBoost have a well known design flaw. Ford only utilizes 8 of the 11 available stud holes on each cylinder head. This creates uneven clamping pressure, often leading to warped manifolds, broken studs, blown gaskets, and eventually, performance loss due to exhaust leaks.

The all-new KC Turbos Upgraded Exhaust Manifolds for your 3.5 EcoBoost addresses these issues with a completely redesigned manifold that uses all 11 stud locations for a more secure, even seal against the cylinder head. Made from high-silicon molybdenum cast iron, our upgraded manifolds are significantly more resistant to thermal warping and cracking under extreme conditions.

Internally, the exhaust runners have been port-matched and redesigned to increase flow by over 30% compared to stock manifolds. This not only improves overall performance but also reduces back pressure and enhances turbo efficiency. The mounting flange thickness has been increased significantly to eliminate common stress points and ensure reliable sealing, while the turbo mounting face has been re-engineered for better alignment and clamping under load. The larger, fully machined sealing surface minimizes hot spots and helps prevent cracking due to uneven heat distribution.

Each kit includes 22 stainless steel studs and spacers to ensure proper thermal expansion and even torque retention. The manifolds are coated in a raw forging state before final machining, ensuring accurate fitment right out of the box.

This isn’t just a repair—it’s a long-term performance solution. Whether you're addressing common failure points or pushing your 3.5L EcoBoost for more power, the KC Turbos Upgraded Exhaust Manifold kit is built to last and perform.