Wehrli 01-04 Chevrolet 6.6L LB7 Duramax High Flow Intake Bundle Kit - Gun Metal

Running a stock intake tract on the 2001-2004 LB7 Duramax means living with undersized piping, restrictive factory rubber boots, and a down pipe full of crushed spots. Wehrli Custom Fab's Stage 3 High Flow Intake Bundle Kit addresses all of that for the Silverado 2500 HD, Silverado 3500, Sierra 2500 HD, and Sierra 3500, finished here in Gun Metal powder coat.

The kit starts with a 4" fabricated aluminum air intake pipe and 10-gauge aluminum air box that draws cold air through the inner fender instead of pulling hot air from the engine bay. A dry filter and hydrophobic Outerwears pre-filter cover keep the MAF sensor and turbo airways free of contaminants, and the removable air box lid makes maintenance simple. The included 4" high flow turbo intake horn opens up the factory turbo mouthpiece restriction and works with OEM and IHI-style upgraded drop-in turbochargers.

Between the turbo and engine, Wehrli replaces the OEM Y-bridge and both intercooler pipes with 3" mandrel-bent aluminum tubing feeding a TIG-welded, CNC-machined billet Y-bridge base. That consistent 3" diameter through the entire intercooler tract helps the turbo build boost more efficiently, improves throttle response, and can lower exhaust gas temperatures. Upgraded silicone boots rated for higher boost pressures and temperatures replace the factory rubber boots known to crack and leak, secured by stainless steel T-bolt clamps.

On the exhaust side, the 3" high flow down pipe takes a straight shot compared to the factory piece, wearing a black ceramic coat with heat wrap to manage under-hood temperatures. The FPRV block-off kit clears the larger Y-bridge assembly, and all hardware and gaskets are included. Not for S300 or S400 turbochargers. Not CARB approved.