Wehrli WCF100304-GB Stage 2 4in Intake Kit w/Air Box for 2011-2016 GM 6.6L LML

Vehicle Fitment

• 2011-2016 Chevrolet Silverado 2500 HD / 3500 HD (6.6L Duramax LML)
• 2011-2016 GMC Sierra 2500 HD / 3500 HD (6.6L Duramax LML)

Fitment Notes

• 2011 model year trucks must update the PCV Regulating Valve to 2012-2016 model year spec before installing this kit
• Not compatible with aftermarket LML Y-bridges that change the manifold/bridge inlet from the original factory driver-side inlet location
• Air box is NOT compatible with intake pipes from kits WCF100337, WCF100689, or WCF100691
• 4.8" High Flow Intake Horn is compatible with OEM and upgraded drop-in VGT style turbochargers only
• No tuning required - direct bolt-on installation compatible with stock trucks
• Not CARB legal - cannot ship to California
• Replaces GM OEM Part Numbers: 23467660, 20917396, 15819728, 25881207, 20847795, 23210121, 22870902

Features

• 37% improvement in airflow over stock intake - 4" aluminum pipe with smooth aerodynamic mandrel bends
• 5.6% additional improvement over stock intake horn via included 4.8" High Flow Cast Aluminum Turbo Intake Horn
• High Flow Intake Horn eliminates the factory resonator for improved underhood appearance and more aggressive turbo sound
• Air box and lid constructed from 10-gauge aluminum sheet for rigid, durable cold air enclosure
• Draws cold air from the inner fender for reduced intake temperatures and improved throttle response
• Removable air box lid for easy filter inspection and maintenance
• Gloss Black custom powder coat finish - handcrafted in the USA

Specifications

• Intake Pipe Diameter: 4"
• Intake Horn Diameter: 4.8" (Cast Aluminum, High Flow)
• Air Box / Lid Material: 10-gauge aluminum sheet
• Intake Pipe Material: 14-gauge aluminum
• Filter Type: Dry Air Filter
• Finish: Gloss Black Custom Powder Coat
• Airflow Improvement: 37% over OEM intake / 5.6% over OEM intake horn
• Hardware: Stainless Steel T-Bolt Clamps (included)
• Emissions: Not CARB Legal - 50-state legal except California

Included Components

• 1x 4" Fabricated Aluminum Intake Pipe
• 1x 4.8" High Flow Cast Aluminum Turbo Intake Horn
• 1x Aluminum Air Box Enclosure with Removable Lid (10-gauge)
• 1x Dry Air Filter
• 1x Outerwear's Hydrophobic Pre-Filter Cover
• 1x Silicone Boot
• 1x Stainless Steel T-Bolt Clamp Set
• 1x Installation Hardware Kit

Product Description

The Wehrli Custom Fabrication WCF100304-GB is the Stage 2 upgrade over the standard WCF100194 intake kit, adding a 4.8" High Flow Cast Aluminum Turbo Intake Horn to the proven 4" intake pipe and enclosed air box system for the 2011-2016 GM 6.6L Duramax LML. Together, the 4" intake pipe and 4.8" intake horn deliver a combined 37% improvement in airflow over the OEM intake and an additional 5.6% gain over the stock intake horn. The high flow horn eliminates the factory plastic resonator, improving underhood appearance and producing a more aggressive turbo and engine sound during acceleration while remaining compatible with OEM and drop-in VGT style turbochargers.

The enclosed 10-gauge aluminum air box draws cold air through the inner fender to lower intake temperatures and reduce heat soak, while the removable lid makes filter inspection straightforward. Finished in Gloss Black custom powder coat and handcrafted in the USA, this kit installs with basic hand tools and requires no tuning. Note: 2011 model year trucks must update the PCV Regulating Valve to 2012-2016 spec prior to installation, and this kit is not compatible with aftermarket LML Y-bridges that relocate the manifold inlet from the factory driver-side location.