Wehrli 20-24 Chevrolet 6.6L Duramax L5P Stage 3 High Flow Intake Bundle Kit - Semi-Gloss Black

Wehrli Custom Fabrication has built a reputation around L5P Duramax aftermarket parts, and this Stage 3 High Flow Bundle in Semi-Gloss Black is their most complete airflow package for the 2020-2025 Silverado and Sierra HD trucks. It covers intake, intercooler, and exhaust plumbing in one kit.

At the front, a 4 in. aluminum intake pipe feeds a fabricated air box enclosure with dry filter element and Outerwears hydrophobic pre-filter. The 4 in. intake horn is over an inch larger than stock, pulling cold air through the factory hood ram air duct. After the turbo, the kit replaces both intercooler pipes: a 3 in. one-piece hot side unit that eliminates the stock 2.5 in. two-piece with its resonator and middle joint, and a 3.5 in. cold side pipe with CNC machined flange and double o-ring seal instead of the factory plastic piece. All piping is 14 ga. aluminum with mandrel bends, joined by reinforced silicone boots and stainless t-bolt clamps.

The 3.5 in. ceramic coated down pipe with pre-installed heat wrap replaces the restrictive factory unit, connecting at the DOC outlet and the OEM 4-bolt front pipe flange. All sensor locations are retained. No tune is needed, and the kit is made in the USA. Semi-Gloss Black gives a clean, understated look under the hood.