What is the benefit of the 3-inch piping over stock?

The factory LB7 intake tract uses smaller, more restrictive piping with tight bends. Wehrli's 3" mandrel-bent aluminum piping creates a smoother, larger path for air to flow between the turbo and engine, which helps improve throttle response, turbo spool, and can help reduce exhaust gas temperatures.

Do I need to buy anything else for installation?

The kit includes all piping, the air box with filter, intake horn, silicone boots, T-bolt clamps, FPRV block-off kit, gaskets, and mounting hardware. Basic hand tools are needed, and you should refer to Wehrli's installation instructions for the full procedure.

Why is the FPRV block-off kit included?

The FPRV (Fuel Pressure Regulator Valve) block-off kit is needed to provide proper clearance for the larger-diameter Y-bridge assembly. Without it, the Y-bridge may interfere with the fuel pressure regulator valve.

Will the Flat Black finish hold up in the engine bay?

The powder coat finish is applied to all aluminum piping components and is built to withstand the heat and conditions of a diesel engine bay. The down pipe uses a separate black ceramic coat with heat wrap for the higher exhaust temperatures it sees.

Specifications

Brand: Wehrli
Part #: WCF100712-FB
UPC: WCF100712-FB

Wehrli 01-04 Chevrolet 6.6L LB7 Duramax High Flow Intake Bundle Kit - Flat Black

Name: Wehrli 01-04 Chevrolet 6.6L LB7 Duramax High Flow Intake Bundle Kit - Flat Black
Brand: Wehrli
SKU: wehrli-wehrli-01-04-chevrolet-6-6l-lb7-duramax-high-flow-intake-bundle-kit-flat--t14-478790
Price: 2139.14 USD
Availability: BackOrder

$2139.14

On Backorder

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Fits 2001-2004 Chevy Silverado and GMC Sierra 6.6L LB7 Duramax. Complete Stage 3 intake bundle in Flat Black powder coat.

Key Features

Fits 2001-2004 Chevrolet Silverado 2500 HD, Silverado 3500, GMC Sierra 2500 HD, and Sierra 3500 with the 6.6L LB7 Duramax.
Stage 3 bundle includes intake, intercooler piping, and down pipe.
4" air intake with 10-gauge aluminum air box and dry filter with Outerwears pre-filter cover.
3" mandrel-bent aluminum intercooler piping with TIG-welded, CNC-machined billet Y-bridge.
4" high flow turbo intake horn for OEM and IHI-style turbochargers.
3" high flow down pipe with black ceramic coat and heat wrap.

⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more

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Will this fit your vehicle?

Advanced difficulty to install

Involves removing factory intake, intercooler pipes, Y-bridge, and down pipe; experience with diesel truck modifications is recommended.

About this part

Product Details

Wehrli Custom Fab has been building intake kits for the LB7 Duramax platform for years, and this Stage 3 High Flow Intake Bundle Kit represents their most complete package for 2001-2004 Silverado 2500 HD, Silverado 3500, Sierra 2500 HD, and Sierra 3500 trucks. Finished in Flat Black powder coat, this kit addresses every major airflow restriction from the filter to the down pipe.

On the intake side, a 4" fabricated aluminum pipe and enclosed air box made from 10-gauge aluminum sheet replace the restrictive plastic factory components. The air box draws cold air through the inner fender and houses a dry filter with a hydrophobic Outerwears pre-filter cover to protect the MAF sensor and turbo. The removable lid makes filter checks quick and easy. A 4" high flow intake horn replaces the factory turbo mouthpiece, removing a common bottleneck and supporting both OEM and IHI-style upgraded drop-in turbochargers.

The intercooler piping side of the kit replaces the OEM Y-bridge and both intercooler pipes with 3" mandrel-bent aluminum tubing. Wehrli's TIG-welded, CNC-machined billet Y-bridge base creates a full 3" intake tract between turbo and engine, which helps the turbo spool faster and lowers exhaust gas temperatures under load. Upgraded silicone boots handle the higher boost pressures and heat that come with opening up the intake tract, and stainless steel T-bolt clamps keep everything sealed.

Rounding out the Stage 3 package is a 3" high flow down pipe that takes a much straighter path than the factory piece with its crushed spots and tight bends. It comes finished in black ceramic coat with heat wrap. The kit also includes an FPRV block-off kit for Y-bridge clearance. For OEM and IHI-style turbos only. Not CARB approved.