Cummins
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SKU #: WCF-WCF100191-FB
MPN #: WCF100191-FB
Wehrli Custom Fab 4" Cold Air Intake Kit With Air Box 04.5-05 GM 6.6L Duramax LLY
Description
You can increase your fuel systems but if your air intake doesn't match the added fuel you're burning then you are simply wasting fuel. Increase your Duramax air with Wehrli Custom Fab 4" Cold Air Intake Kit! If you’re looking to wake up your LLY Duramax, airflow is one of the first places to start. The LLY Duramax Cold Air Intake Kit with Air Box is designed to improve airflow, throttle response, and overall engine efficiency while giving your engine bay a clean, custom look.
NOTE: While some colors are kept in stock, other colors will take an extra 10-15 business day delay in powder coating.
This intake system replaces the restrictive factory air box with a high-flow intake design and sealed air box, helping deliver cooler, denser air to your turbo. The result is improved performance, better throttle response, and more efficient operation especially under load or towing conditions.
Built with high-quality fabricated components, this kit is designed for durability and long-term reliability. The included air box helps protect the filter from engine bay heat, ensuring consistent performance whether you're daily driving or pushing your truck harder.
Finished in your choice of WCFab custom powder coat colors, this intake doesn’t just perform; it stands out every time you pop the hood.
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About WrenchConnected
WrenchConnected is an independent installation marketplace operating in partnership with Diesel Power Products.
How it works
After checkout, we route your vehicle info and part SKU to verified installation shops near you. Local installers review the job and submit competitive bids; you pick the shop you want based on price, reviews, and availability. Your name and email stay private until you select an installer.
Pricing
You pay for the bid from your preferred shop. The full amount is shown before you confirm — installers cannot add charges without your written consent. Payments are processed securely by Stripe.
Your privacy
During bidding, shops see only your service ZIP code, vehicle year/make/model, and the part SKU — not your name, email, or address. Only the shop you select receives your contact details after payment. We never sell your personal information.
More detail at wrenchconnected.com.
FEATURES & BENEFITS:
- Improves airflow and throttle response
- Sealed air box design helps reduce intake air temperatures
- High-quality fabricated construction for durability
- Reusable high-flow air filter
- Custom powder coat finish options
- Direct bolt-on installation
About Wehrli Custom Fabrication
Born from a garage dream in Sandwich, Illinois, and now headquartered in DeKalb, Illinois, Wehrli Custom Fabrication (WCFab) has earned a formidable reputation in the diesel performance world. From its hands-on beginnings to its expansion into a team of 50-plus skilled builders, WCFab continues to elevate diesel upgrades, even as the brand evolves into fabrication and powder coating excellence.
At its core, Wehrli is dedicated to powering Duramax, Powerstroke, and Cummins trucks with rugged, high-performance parts that meet the real-world demands of hauling, towing, and racing. Every product is proudly Made in the USA, from turbo kits and cold air intakes to heavy-duty Allison transmission builds capable of handling up to 750hp, thoroughly crafted in a climate-controlled clean room.
Whether you’re upping airflow with precision CNC-machined intakes and intake horns, clearing the engine bay with billet block-off plates, or commanding raw transportation power with a 750+hp Allison transmission, Wehrli’s work is synonymous with resilience and peak performance. Products like their L5P Duramax high-flow turbo intake horn boast a 27% increase in flow, proving that function and form can coexist beautifully.
Customer support is a serious affair at WCFab they stand firmly behind their fits and finishes Led by the Wehrli brothers and a crew fueled by diesel passion, the brand’s mission is clear: deliver top-tier craftsmanship, unmatched performance, and relentless customer service.
Wehrli Custom Fabrication—where diesel dreams are forged into reality, in metal you can feel and performance you can trust.
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