Wehrli 01-04 Chevrolet 6.6L LB7 Duramax High Flow Intake Bundle Kit - Bengal Red

All-aluminum construction with large-diameter 4-inch piping is at the core of Wehrli Custom Fab's Stage 3 High Flow Intake Bundle for the 2001-2004 Chevrolet Silverado 2500 HD, Silverado 3500, GMC Sierra 2500 HD, and Sierra 3500 with the 6.6L LB7 Duramax. This Bengal Red powder coat version bundles the Stage 1 intake, Stage 2 intercooler piping, and 3-inch downpipe together to replace the entire restrictive factory intake tract.

The 4-inch intake system replaces the plastic factory setup with a fabricated aluminum airbox built from 10-gauge sheet. Cold air draws through the inner fender, keeping intake temperatures down. The included dry filter has a hydrophobic Outerwears pre-filter cover, and the removable airbox lid makes checking on it easy. A 4-inch high flow turbo intake horn removes restrictions from the OEM intake path, improving turbo spool and top-end power for OEM and IHI-style drop-in turbochargers.

The intercooler piping replaces the OEM Y-bridge and both intercooler pipes with 3-inch mandrel-bent aluminum, feeding Wehrli's TIG-welded, CNC-machined billet Y-bridge base. This opens up a full 3-inch intake tract from turbo to engine, which helps improve throttle response and reduce EGTs. The included 3-inch downpipe runs a straight shot compared to the factory unit, improving exhaust flow and cutting under-hood heat. It arrives finished in black ceramic coat with heat wrap.

Silicone boots rated for higher pressures and temperatures replace the failure-prone factory parts, and stainless steel T-bolt clamps secure all connections. An FPRV block-off kit allows clearance for the larger Y-bridge assembly. All hardware and gaskets are included. Not recommended for S300 or S400 turbochargers. Not CARB-approved.