Wehrli Custom Fabrication WCF100535-BRZ 4" High-Flow Cast Aluminum Turbo Intake Horn - Bronze

The Wehrli Custom Fabrication WCF100535 is a 4-inch High-Flow Cast Aluminum Turbo Intake Horn engineered to replace the restrictive OEM turbocharger mouthpiece on the 6.6L Duramax LB7 diesel engine. Precision-crafted in the USA, this intake horn delivers a meaningful increase in airflow to your turbocharger for improved engine performance and throttle response. This listing is for the Bronze (BRZ) custom powder coat finish.

Key Features:

• True 4" inlet with smooth, optimized transition to the turbo compressor cover for maximum airflow and drivability
• Flows 40% better than stock — the largest and highest-flowing turbo inlet available for the LB7 platform
• Precision CNC machined cast aluminum construction for superior strength and durability
• Compatible with factory IHI turbo and upgraded drop-in IHI turbochargers with larger compressor wheels
• Works with performance aftermarket intake systems utilizing a 4" boot connection with bead roll (such as WCFab 4" Intake Kits)
• Delivers quicker turbo spool-up and measurable horsepower gains — max-effort tuned trucks can see 10–15 HP gains; applications with upgraded turbochargers may see up to 20 HP improvements
• Finished in a durable custom Bronze powder coat for a distinctive, long-lasting appearance under the hood
• Made in the USA by Wehrli Custom Fabrication in DeKalb, Illinois

Important Notes:

• Not compatible with OEM intake fitment
• Requires an aftermarket intake system with a removable 4" boot connection featuring a bead roll — intakes with a molded-in rubber/silicone connection are not compatible

For maximum performance, pair the WCF100535 with a WCFab 4" Cold Air Intake Kit and Stage 1 High Flow Bundle Kit. This intake horn is a straightforward bolt-on upgrade — no tuning required for installation.